diff --git a/admin/api_keys.php b/admin/api_keys.php
index 550bd03..ccc0c24 100644
--- a/admin/api_keys.php
+++ b/admin/api_keys.php
@@ -115,17 +115,17 @@ $adminBase   = '';
         <p class="muted"><?= __('api_none') ?></p>
     <?php else: ?>
     <div class="table-container">
-    <table>
+    <table class="table-stack">
         <tr><th><?= __('label_name') ?></th><th><?= __('api_col_prefix') ?></th><th><?= __('api_col_scope') ?></th><th><?= __('api_col_limit') ?></th><th><?= __('label_status') ?></th><th><?= __('api_col_last_used') ?></th><th><?= __('api_col_created_by') ?></th><th></th></tr>
         <?php foreach ($keys as $k): ?>
         <tr>
-            <td><?= htmlspecialchars($k['name']) ?></td>
-            <td><code>uvt_<?= htmlspecialchars($k['key_prefix']) ?>…</code></td>
-            <td><?= ($k['scope'] ?? 'write') === 'read' ? __('api_scope_read_short') : __('api_scope_write_short') ?></td>
-            <td><?= (int)($k['rate_limit'] ?? 0) === 0 ? '∞' : (int)$k['rate_limit'] . '/min' ?></td>
-            <td><span class="badge <?= $k['is_active'] ? 'b-on' : 'b-off' ?>"><?= $k['is_active'] ? __('api_state_active') : __('api_state_blocked') ?></span></td>
-            <td class="muted"><?= $k['last_used_at'] ? date('d.m.Y H:i', strtotime($k['last_used_at'])) : '–' ?></td>
-            <td class="muted"><?= htmlspecialchars($k['creator'] ?? '–') ?></td>
+            <td data-label="<?= __('label_name') ?>"><?= htmlspecialchars($k['name']) ?></td>
+            <td data-label="<?= __('api_col_prefix') ?>"><code>uvt_<?= htmlspecialchars($k['key_prefix']) ?>…</code></td>
+            <td data-label="<?= __('api_col_scope') ?>"><?= ($k['scope'] ?? 'write') === 'read' ? __('api_scope_read_short') : __('api_scope_write_short') ?></td>
+            <td data-label="<?= __('api_col_limit') ?>"><?= (int)($k['rate_limit'] ?? 0) === 0 ? '∞' : (int)$k['rate_limit'] . '/min' ?></td>
+            <td data-label="<?= __('label_status') ?>"><span class="badge <?= $k['is_active'] ? 'b-on' : 'b-off' ?>"><?= $k['is_active'] ? __('api_state_active') : __('api_state_blocked') ?></span></td>
+            <td class="muted" data-label="<?= __('api_col_last_used') ?>"><?= $k['last_used_at'] ? date('d.m.Y H:i', strtotime($k['last_used_at'])) : '–' ?></td>
+            <td class="muted" data-label="<?= __('api_col_created_by') ?>"><?= htmlspecialchars($k['creator'] ?? '–') ?></td>
             <td style="text-align:right;white-space:nowrap;">
                 <a class="a-link" href="?toggle=<?= (int)$k['id'] ?>&token=<?= urlencode($csrf) ?>"><?= $k['is_active'] ? __('api_action_block') : __('api_action_unblock') ?></a>
                 <a class="a-link" style="color:var(--danger);" href="?delete=<?= (int)$k['id'] ?>&token=<?= urlencode($csrf) ?>" onclick="return confirm('<?= __('api_delete_confirm') ?>');"><?= __('btn_delete') ?></a>
diff --git a/admin/audit_log.php b/admin/audit_log.php
index 551a042..52d2937 100644
--- a/admin/audit_log.php
+++ b/admin/audit_log.php
@@ -71,7 +71,7 @@ foreach (['voucher_created', 'voucher_bulk', 'user_login', 'user_logout', 'user_
 
     <!-- Filter -->
     <div class="card" style="margin-bottom: 20px;">
-        <div class="card-header"><span class="card-title"><i class="fas fa-filter"></i> <?= __('audit_filter') ?></span></div>
+        <div class="card-header"><span class="card-title"><i class="fas fa-filter" aria-hidden="true"></i> <?= __('audit_filter') ?></span></div>
         <div style="padding: 20px 25px;">
             <form method="get" class="filter-bar">
                 <div>
@@ -96,8 +96,8 @@ foreach (['voucher_created', 'voucher_bulk', 'user_login', 'user_logout', 'user_
                         <?php endforeach; ?>
                     </select>
                 </div>
-                <button type="submit" class="btn btn-primary btn-small"><i class="fas fa-search"></i> Filtern</button>
-                <a href="audit_log.php" class="btn btn-secondary btn-small"><i class="fas fa-times"></i> Zurücksetzen</a>
+                <button type="submit" class="btn btn-primary btn-small"><i class="fas fa-search" aria-hidden="true"></i> Filtern</button>
+                <a href="audit_log.php" class="btn btn-secondary btn-small"><i class="fas fa-times" aria-hidden="true"></i> Zurücksetzen</a>
             </form>
         </div>
     </div>
@@ -105,15 +105,15 @@ foreach (['voucher_created', 'voucher_bulk', 'user_login', 'user_logout', 'user_
     <!-- Log-Tabelle -->
     <div class="card">
         <div class="card-header">
-            <span class="card-title"><i class="fas fa-history"></i> <?= __('audit_title') ?></span>
+            <span class="card-title"><i class="fas fa-history" aria-hidden="true"></i> <?= __('audit_title') ?></span>
             <span style="font-size:13px;color:var(--text-muted);"><?= number_format($total) ?> Einträge</span>
         </div>
         <?php if (empty($logs)): ?>
-            <div class="empty-state"><i class="fas fa-history"></i><p><?= __('audit_none') ?></p></div>
+            <div class="empty-state"><i class="fas fa-history" aria-hidden="true"></i><p><?= __('audit_none') ?></p></div>
         <?php else: ?>
         <div style="overflow-x:auto;">
             <div class="table-container">
-            <table class="table">
+            <table class="table table-stack">
                 <thead>
                     <tr>
                         <th><?= __('audit_time') ?></th>
@@ -127,34 +127,34 @@ foreach (['voucher_created', 'voucher_bulk', 'user_login', 'user_logout', 'user_
                 <tbody>
                     <?php foreach ($logs as $log): ?>
                     <tr>
-                        <td style="white-space:nowrap;color:var(--text-muted);">
+                        <td data-label="<?= __('audit_time') ?>" style="white-space:nowrap;color:var(--text-muted);">
                             <?= date('d.m.Y', strtotime($log['created_at'])) ?><br>
                             <small><?= date('H:i:s', strtotime($log['created_at'])) ?></small>
                         </td>
-                        <td>
+                        <td data-label="<?= __('audit_action') ?>">
                             <span class="action-chip">
                                 <?= htmlspecialchars($actionLabels[$log['action']] ?? $log['action']) ?>
                             </span>
                         </td>
-                        <td>
+                        <td data-label="<?= __('audit_user') ?>">
                             <?php if ($log['user_name']): ?>
                                 <strong style="font-size:13px;"><?= htmlspecialchars($log['user_name']) ?></strong><br>
                                 <small style="color:var(--text-muted);"><?= htmlspecialchars($log['user_email'] ?? '') ?></small>
                             <?php else: ?>
-                                <em style="color:var(--text-muted);">System/Anonym</em>
+                                <em style="color:var(--text-muted);"><?= __('audit_system_anon') ?></em>
                             <?php endif; ?>
                         </td>
-                        <td style="color:var(--text-secondary);">
+                        <td data-label="<?= __('audit_entity') ?>" style="color:var(--text-secondary);">
                             <?php if ($log['entity_type']): ?>
                                 <code style="font-size:11px;"><?= htmlspecialchars($log['entity_type']) ?>:<?= htmlspecialchars($log['entity_id'] ?? '') ?></code>
                             <?php else: ?>
                                 <span style="color:var(--text-muted);">-</span>
                             <?php endif; ?>
                         </td>
-                        <td class="details-cell" title="<?= htmlspecialchars($log['details'] ?? '') ?>">
+                        <td class="details-cell" data-label="<?= __('audit_details') ?>" title="<?= htmlspecialchars($log['details'] ?? '') ?>">
                             <?= htmlspecialchars(mb_strimwidth($log['details'] ?? '-', 0, 80, '…')) ?>
                         </td>
-                        <td class="ip-cell"><?= htmlspecialchars($log['ip_address'] ?? '-') ?></td>
+                        <td class="ip-cell" data-label="<?= __('audit_ip') ?>"><?= htmlspecialchars($log['ip_address'] ?? '-') ?></td>
                     </tr>
                     <?php endforeach; ?>
                 </tbody>
@@ -169,13 +169,13 @@ foreach (['voucher_created', 'voucher_bulk', 'user_login', 'user_logout', 'user_
                 <?php
                 $baseUrl = '?' . http_build_query(array_filter(['action' => $filterAction, 'user_id' => $filterUser]));
                 if ($page > 1): ?>
-                    <a href="<?= $baseUrl ?>&page=<?= $page - 1 ?>" class="page-btn"><i class="fas fa-chevron-left"></i></a>
+                    <a href="<?= $baseUrl ?>&page=<?= $page - 1 ?>" class="page-btn"><i class="fas fa-chevron-left" aria-hidden="true"></i></a>
                 <?php endif;
                 for ($p = max(1, $page - 2); $p <= min($pages, $page + 2); $p++): ?>
                     <a href="<?= $baseUrl ?>&page=<?= $p ?>" class="page-btn <?= $p === $page ? 'active' : '' ?>"><?= $p ?></a>
                 <?php endfor;
                 if ($page < $pages): ?>
-                    <a href="<?= $baseUrl ?>&page=<?= $page + 1 ?>" class="page-btn"><i class="fas fa-chevron-right"></i></a>
+                    <a href="<?= $baseUrl ?>&page=<?= $page + 1 ?>" class="page-btn"><i class="fas fa-chevron-right" aria-hidden="true"></i></a>
                 <?php endif; ?>
             </div>
         </div>
diff --git a/admin/index.php b/admin/index.php
index 7f743d6..4f3ee40 100644
--- a/admin/index.php
+++ b/admin/index.php
@@ -105,7 +105,7 @@ $currentPage = 'dashboard';
             <span id="liveStatus">DB</span>
         </span>
         <button onclick="refreshData('live')" class="btn btn-secondary btn-sm" id="refreshBtn">
-            <i class="fas fa-sync-alt"></i> <?= __('dashboard_live_refresh') ?>
+            <i class="fas fa-sync-alt" aria-hidden="true"></i> <?= __('dashboard_live_refresh') ?>
         </button>
     </div>
 </div>
@@ -114,21 +114,21 @@ $currentPage = 'dashboard';
     <div class="stat-card">
         <div class="stat-card-header">
             <div class="stat-card-title"><?= __('dashboard_active_sites') ?></div>
-            <div class="stat-card-icon info"><i class="fas fa-location-dot"></i></div>
+            <div class="stat-card-icon info"><i class="fas fa-location-dot" aria-hidden="true"></i></div>
         </div>
         <div class="stat-card-value"><?= $stats['total_sites'] ?></div>
     </div>
     <div class="stat-card">
         <div class="stat-card-header">
             <div class="stat-card-title"><?= __('dashboard_users') ?></div>
-            <div class="stat-card-icon accent"><i class="fas fa-users"></i></div>
+            <div class="stat-card-icon accent"><i class="fas fa-users" aria-hidden="true"></i></div>
         </div>
         <div class="stat-card-value"><?= $stats['total_users'] ?></div>
     </div>
     <div class="stat-card live">
         <div class="stat-card-header">
             <div class="stat-card-title"><?= __('dashboard_valid') ?></div>
-            <div class="stat-card-icon success"><i class="fas fa-circle-check"></i></div>
+            <div class="stat-card-icon success"><i class="fas fa-circle-check" aria-hidden="true"></i></div>
         </div>
         <div class="stat-card-value valid" id="liveValid"><?= (int)($voucherStats['valid']??0) ?></div>
         <div class="stat-card-sub" id="subValid"><?= $lastCronSync ? date('H:i', strtotime($lastCronSync)) : __('never') ?></div>
@@ -136,21 +136,21 @@ $currentPage = 'dashboard';
     <div class="stat-card live">
         <div class="stat-card-header">
             <div class="stat-card-title"><?= __('dashboard_used') ?></div>
-            <div class="stat-card-icon warning"><i class="fas fa-user-check"></i></div>
+            <div class="stat-card-icon warning"><i class="fas fa-user-check" aria-hidden="true"></i></div>
         </div>
         <div class="stat-card-value used" id="liveUsed"><?= (int)($voucherStats['used']??0) ?></div>
     </div>
     <div class="stat-card live">
         <div class="stat-card-header">
             <div class="stat-card-title"><?= __('dashboard_expired') ?></div>
-            <div class="stat-card-icon danger"><i class="fas fa-circle-xmark"></i></div>
+            <div class="stat-card-icon danger"><i class="fas fa-circle-xmark" aria-hidden="true"></i></div>
         </div>
         <div class="stat-card-value expired" id="liveExpired"><?= (int)($voucherStats['expired']??0) ?></div>
     </div>
     <div class="stat-card live">
         <div class="stat-card-header">
             <div class="stat-card-title"><?= __('dashboard_total') ?></div>
-            <div class="stat-card-icon"><i class="fas fa-ticket"></i></div>
+            <div class="stat-card-icon"><i class="fas fa-ticket" aria-hidden="true"></i></div>
         </div>
         <div class="stat-card-value" id="liveTotal"><?= (int)($voucherStats['total']??0) ?></div>
     </div>
@@ -183,9 +183,9 @@ $currentPage = 'dashboard';
             <?php endforeach; ?>
             <?php if (empty($sites)): ?>
             <div class="empty-state" style="grid-column:1/-1;">
-                <div class="empty-icon"><i class="fas fa-location-dot"></i></div>
+                <div class="empty-icon"><i class="fas fa-location-dot" aria-hidden="true"></i></div>
                 <p><?= __('dashboard_no_data') ?></p>
-                <a href="sites.php" class="btn btn-primary" style="margin-top:15px;"><i class="fas fa-plus"></i> <?= __('sites_add') ?></a>
+                <a href="sites.php" class="btn btn-primary" style="margin-top:15px;"><i class="fas fa-plus" aria-hidden="true"></i> <?= __('sites_add') ?></a>
             </div>
             <?php endif; ?>
         </div>
@@ -204,7 +204,7 @@ $currentPage = 'dashboard';
         <div class="card-header"><h2 class="card-title"><?= __('dashboard_top_users') ?></h2></div>
         <div class="card-body">
             <?php if (empty($topUsers)): ?>
-                <div class="empty-state"><i class="fas fa-users"></i><p><?= __('dashboard_no_data') ?></p></div>
+                <div class="empty-state"><i class="fas fa-users" aria-hidden="true"></i><p><?= __('dashboard_no_data') ?></p></div>
             <?php else: ?>
                 <ul class="top-users-list">
                     <?php foreach ($topUsers as $u): ?>
@@ -225,21 +225,21 @@ $currentPage = 'dashboard';
     </div>
 
     <div class="card">
-        <div class="card-header"><h2 class="card-title"><?= __('dashboard_recent') ?></h2><a href="vouchers.php" class="btn btn-secondary btn-sm"><i class="fas fa-arrow-up-right-from-square"></i> Live</a></div>
+        <div class="card-header"><h2 class="card-title"><?= __('dashboard_recent') ?></h2><a href="vouchers.php" class="btn btn-secondary btn-sm"><i class="fas fa-arrow-up-right-from-square" aria-hidden="true"></i> Live</a></div>
         <div class="card-body" style="padding:0;">
             <?php if (empty($recentVouchers)): ?>
-                <div class="empty-state"><i class="fas fa-ticket-alt"></i><p><?= __('dashboard_no_vouchers') ?></p></div>
+                <div class="empty-state"><i class="fas fa-ticket-alt" aria-hidden="true"></i><p><?= __('dashboard_no_vouchers') ?></p></div>
             <?php else: ?>
                 <div class="table-container">
-                <table class="table">
+                <table class="table table-stack">
                     <thead><tr><th><?= __('label_created') ?></th><th><?= __('label_code') ?></th><th><?= __('label_site') ?></th><th><?= __('label_status') ?></th></tr></thead>
                     <tbody>
                         <?php foreach ($recentVouchers as $v): ?>
                         <tr>
-                            <td style="font-size:12px;"><?= date('d.m H:i', strtotime($v['created_at'])) ?></td>
-                            <td><code><?= htmlspecialchars($v['voucher_code']) ?></code></td>
-                            <td><span class="badge badge-info"><?= htmlspecialchars($v['site_name']??'') ?></span></td>
-                            <td>
+                            <td data-label="<?= __('label_created') ?>" style="font-size:12px;"><?= date('d.m H:i', strtotime($v['created_at'])) ?></td>
+                            <td data-label="<?= __('label_code') ?>"><code><?= htmlspecialchars($v['voucher_code']) ?></code></td>
+                            <td data-label="<?= __('label_site') ?>"><span class="badge badge-info"><?= htmlspecialchars($v['site_name']??'') ?></span></td>
+                            <td data-label="<?= __('label_status') ?>">
                                 <?php $st=$v['status']??'valid'; ?>
                                 <span class="badge badge-<?= $st==='valid'?'success':($st==='used'?'warning':'danger') ?>"><?= __('status_'.$st) ?></span>
                             </td>
@@ -255,7 +255,7 @@ $currentPage = 'dashboard';
 
 </main>
 
-<div id="toast-container"></div>
+<div id="toast-container" role="status" aria-live="polite"></div>
 <script src="../assets/global.js"></script>
 <script>
 const rootStyles = getComputedStyle(document.documentElement);
@@ -302,7 +302,7 @@ async function refreshData(mode='db') {
     liveBadge.className = 'live-badge loading';
     liveStatus.textContent = '...';
     refreshBtn.disabled = true;
-    refreshBtn.innerHTML = '<i class="fas fa-spinner fa-spin"></i>';
+    refreshBtn.innerHTML = '<i class="fas fa-spinner fa-spin" aria-hidden="true"></i>';
     try {
         const url = `index.php?ajax_stats=1${mode==='live'?'&sync=1':''}`;
         const result = await fetch(url).then(r=>r.json());
@@ -340,7 +340,7 @@ async function refreshData(mode='db') {
     }
     isLoading = false;
     refreshBtn.disabled = false;
-    refreshBtn.innerHTML = '<i class="fas fa-sync-alt"></i> <?= __('dashboard_live_refresh') ?>';
+    refreshBtn.innerHTML = '<i class="fas fa-sync-alt" aria-hidden="true"></i> <?= __('dashboard_live_refresh') ?>';
 }
 </script>
 </body>
diff --git a/admin/reports.php b/admin/reports.php
index cfd7d51..7b2aebf 100644
--- a/admin/reports.php
+++ b/admin/reports.php
@@ -115,10 +115,10 @@ $adminBase   = '';
             <?php endforeach; ?>
         </select>
     </form>
-    <a class="btn btn-secondary" href="?export=daily&days=<?= $days ?>"><i class="fas fa-download"></i> <?= __('rep_csv_daily') ?></a>
-    <a class="btn btn-secondary" href="?export=per_site"><i class="fas fa-download"></i> <?= __('rep_csv_site') ?></a>
-    <a class="btn btn-secondary" href="?export=per_user"><i class="fas fa-download"></i> <?= __('rep_csv_user') ?></a>
-    <button class="btn btn-secondary" onclick="window.print()"><i class="fas fa-print"></i> <?= __('rep_print') ?></button>
+    <a class="btn btn-secondary" href="?export=daily&days=<?= $days ?>"><i class="fas fa-download" aria-hidden="true"></i> <?= __('rep_csv_daily') ?></a>
+    <a class="btn btn-secondary" href="?export=per_site"><i class="fas fa-download" aria-hidden="true"></i> <?= __('rep_csv_site') ?></a>
+    <a class="btn btn-secondary" href="?export=per_user"><i class="fas fa-download" aria-hidden="true"></i> <?= __('rep_csv_user') ?></a>
+    <button class="btn btn-secondary" onclick="window.print()"><i class="fas fa-print" aria-hidden="true"></i> <?= __('rep_print') ?></button>
 </div>
 
 <div class="grid4">
diff --git a/admin/security.php b/admin/security.php
index d71fcc3..3de454c 100644
--- a/admin/security.php
+++ b/admin/security.php
@@ -104,7 +104,7 @@ $activeSessions = $dbSessions ? $auth->activeSessionCount() : 0;
 <body class="app-body focus-page">
 <div class="focus-card card">
   <div class="focus-head">
-    <span class="focus-icon"><i class="fas fa-shield-halved"></i></span>
+    <span class="focus-icon"><i class="fas fa-shield-halved" aria-hidden="true"></i></span>
     <div>
       <h1><?= __('sec_title') ?></h1>
       <p class="sub"><?= __('sec_account') ?> <?= htmlspecialchars($user['email']) ?></p>
@@ -119,7 +119,7 @@ $activeSessions = $dbSessions ? $auth->activeSessionCount() : 0;
 
   <?php if (!empty($backupCodes)): ?>
     <div class="codes-box">
-      <strong><i class="fas fa-key"></i> <?= __('sec_recovery_codes') ?></strong>
+      <strong><i class="fas fa-key" aria-hidden="true"></i> <?= __('sec_recovery_codes') ?></strong>
       <p><?= __('sec_recovery_hint') ?></p>
       <div class="codes">
         <?php foreach ($backupCodes as $c): ?><span><?= htmlspecialchars($c) ?></span><?php endforeach; ?>
@@ -128,10 +128,10 @@ $activeSessions = $dbSessions ? $auth->activeSessionCount() : 0;
   <?php endif; ?>
 
   <?php if (!$hasPassword): ?>
-    <div class="status off"><i class="fas fa-circle-minus"></i> <?= __('sec_unavailable') ?></div>
+    <div class="status off"><i class="fas fa-circle-minus" aria-hidden="true"></i> <?= __('sec_unavailable') ?></div>
     <p class="sub"><?= __('sec_m365_hint') ?></p>
   <?php elseif ($totpEnabled): ?>
-    <div class="status on"><i class="fas fa-circle-check"></i> <?= __('sec_active') ?></div>
+    <div class="status on"><i class="fas fa-circle-check" aria-hidden="true"></i> <?= __('sec_active') ?></div>
     <p class="sub"><?= __('sec_active_hint') ?><br>
        <?= __('sec_codes_left') ?> <strong><?= (int)$auth->backupCodesRemaining($user) ?></strong></p>
     <form method="post" style="margin-bottom:10px;">
@@ -143,7 +143,7 @@ $activeSessions = $dbSessions ? $auth->activeSessionCount() : 0;
       <button type="submit" name="disable_totp" class="btn btn-danger btn-lg btn-block"><?= __('sec_disable') ?></button>
     </form>
   <?php else: ?>
-    <div class="status off"><i class="fas fa-circle-minus"></i> <?= __('sec_inactive') ?></div>
+    <div class="status off"><i class="fas fa-circle-minus" aria-hidden="true"></i> <?= __('sec_inactive') ?></div>
     <ol>
       <li><?= __('sec_step_1') ?></li>
       <li><?= __('sec_step_2') ?></li>
@@ -175,7 +175,7 @@ $activeSessions = $dbSessions ? $auth->activeSessionCount() : 0;
   </form>
   <?php endif; ?>
 
-  <div class="auth-links"><a class="back-link" href="../index.php"><i class="fas fa-arrow-left"></i> <?= __('nav_back') ?></a></div>
+  <div class="auth-links"><a class="back-link" href="../index.php"><i class="fas fa-arrow-left" aria-hidden="true"></i> <?= __('nav_back') ?></a></div>
 </div>
 </body>
 </html>
diff --git a/admin/settings.php b/admin/settings.php
index f6e7a6a..79c2532 100644
--- a/admin/settings.php
+++ b/admin/settings.php
@@ -277,7 +277,7 @@ function imageField(string $name, string $label, string $value, string $hint = '
                 <?php if ($preview !== ''): ?>
                     <img src="<?= htmlspecialchars($preview) ?>" alt="">
                 <?php else: ?>
-                    <i class="fas fa-image"></i>
+                    <i class="fas fa-image" aria-hidden="true"></i>
                 <?php endif; ?>
             </div>
             <div class="image-field-controls">
@@ -318,29 +318,29 @@ $adminBase = '';
     </div>
 
     <?php if ($error): ?>
-        <div class="alert alert-error"><i class="fas fa-exclamation-circle"></i><span><?= htmlspecialchars($error) ?></span></div>
+        <div class="alert alert-error"><i class="fas fa-exclamation-circle" aria-hidden="true"></i><span><?= htmlspecialchars($error) ?></span></div>
     <?php endif; ?>
     <?php if ($success): ?>
-        <div class="alert alert-success"><i class="fas fa-check-circle"></i><span><?= htmlspecialchars($success) ?></span></div>
+        <div class="alert alert-success"><i class="fas fa-check-circle" aria-hidden="true"></i><span><?= htmlspecialchars($success) ?></span></div>
     <?php endif; ?>
 
     <div class="tab-container">
         <div class="tab-navigation" id="tabNav">
-            <button class="tab-button active" data-tab="general"><i class="fas fa-sliders-h"></i> <?= __('settings_tab_general') ?></button>
-            <button class="tab-button" data-tab="defaults"><i class="fas fa-sliders-h"></i> <?= __('settings_tab_defaults') ?></button>
-            <button class="tab-button" data-tab="branding"><i class="fas fa-palette"></i> <?= __('settings_tab_branding') ?></button>
-            <button class="tab-button" data-tab="login"><i class="fas fa-right-to-bracket"></i> <?= __('settings_tab_login') ?></button>
-            <button class="tab-button" data-tab="cron"><i class="fas fa-clock"></i> <?= __('settings_tab_cron') ?></button>
-            <button class="tab-button" data-tab="m365"><i class="fab fa-microsoft"></i> <?= __('settings_tab_m365') ?></button>
-            <button class="tab-button" data-tab="smtp"><i class="fas fa-envelope"></i> <?= __('settings_tab_smtp') ?></button>
-            <button class="tab-button" data-tab="templates_email"><i class="fas fa-file-alt"></i> <?= __('settings_tab_templates_email') ?></button>
-            <button class="tab-button" data-tab="system"><i class="fas fa-cogs"></i> <?= __('settings_tab_system') ?></button>
-            <button class="tab-button" data-tab="password"><i class="fas fa-key"></i> <?= __('settings_tab_password') ?></button>
+            <button class="tab-button active" data-tab="general"><i class="fas fa-sliders-h" aria-hidden="true"></i> <?= __('settings_tab_general') ?></button>
+            <button class="tab-button" data-tab="defaults"><i class="fas fa-sliders-h" aria-hidden="true"></i> <?= __('settings_tab_defaults') ?></button>
+            <button class="tab-button" data-tab="branding"><i class="fas fa-palette" aria-hidden="true"></i> <?= __('settings_tab_branding') ?></button>
+            <button class="tab-button" data-tab="login"><i class="fas fa-right-to-bracket" aria-hidden="true"></i> <?= __('settings_tab_login') ?></button>
+            <button class="tab-button" data-tab="cron"><i class="fas fa-clock" aria-hidden="true"></i> <?= __('settings_tab_cron') ?></button>
+            <button class="tab-button" data-tab="m365"><i class="fab fa-microsoft" aria-hidden="true"></i> <?= __('settings_tab_m365') ?></button>
+            <button class="tab-button" data-tab="smtp"><i class="fas fa-envelope" aria-hidden="true"></i> <?= __('settings_tab_smtp') ?></button>
+            <button class="tab-button" data-tab="templates_email"><i class="fas fa-file-alt" aria-hidden="true"></i> <?= __('settings_tab_templates_email') ?></button>
+            <button class="tab-button" data-tab="system"><i class="fas fa-cogs" aria-hidden="true"></i> <?= __('settings_tab_system') ?></button>
+            <button class="tab-button" data-tab="password"><i class="fas fa-key" aria-hidden="true"></i> <?= __('settings_tab_password') ?></button>
         </div>
 
         <!-- Allgemein -->
         <div id="tab-general" class="tab-content active">
-            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-sliders-h"></i> <?= __('settings_tab_general') ?></h2>
+            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-sliders-h" aria-hidden="true"></i> <?= __('settings_tab_general') ?></h2>
             <form method="post" enctype="multipart/form-data">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
                 <input type="hidden" name="form_type" value="general">
@@ -353,13 +353,13 @@ $adminBase = '';
                 <div class="form-group"><label><?= __('settings_instr_header') ?></label><input type="text" name="instruction_header" value="<?= htmlspecialchars($cs['instruction_header']) ?>"></div>
                 <div class="form-group"><label><?= __('settings_instr_text') ?></label><textarea name="instruction_text" class="tinymce-editor"><?= htmlspecialchars($cs['instruction_text']) ?></textarea></div>
                 <div class="checkbox-group" style="margin-bottom: 20px;"><input type="checkbox" name="public_access" id="public_access" <?= $cs['public_access'] == '1' ? 'checked' : '' ?>><label for="public_access" style="margin:0;"><?= __('settings_public_access') ?></label></div>
-                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
             </form>
         </div>
 
         <!-- Voucher-Standards -->
         <div id="tab-defaults" class="tab-content">
-            <h2 style="margin-bottom: 8px; color: var(--text-primary);"><i class="fas fa-sliders-h"></i> <?= __('settings_tab_defaults') ?></h2>
+            <h2 style="margin-bottom: 8px; color: var(--text-primary);"><i class="fas fa-sliders-h" aria-hidden="true"></i> <?= __('settings_tab_defaults') ?></h2>
             <p style="color: var(--text-muted); font-size: 14px; margin-bottom: 24px;"><?= __('settings_defaults_hint') ?></p>
             <form method="post">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
@@ -382,20 +382,20 @@ $adminBase = '';
                     </div>
                 </div>
                 <div class="info-box" style="margin-top: 10px;">
-                    <h4><i class="fas fa-info-circle"></i> Gültigkeits-Referenz</h4>
+                    <h4><i class="fas fa-info-circle" aria-hidden="true"></i> Gültigkeits-Referenz</h4>
                     <p>
                         60 Min = 1 Stunde &nbsp;|&nbsp; 480 Min = 8 Stunden &nbsp;|&nbsp;
                         1440 Min = 1 Tag &nbsp;|&nbsp; 10080 Min = 1 Woche &nbsp;|&nbsp;
                         43200 Min = 30 Tage
                     </p>
                 </div>
-                <button type="submit" name="save_settings" class="btn btn-primary" style="margin-top: 16px;"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                <button type="submit" name="save_settings" class="btn btn-primary" style="margin-top: 16px;"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
             </form>
         </div>
 
         <!-- Design & Branding -->
         <div id="tab-branding" class="tab-content">
-            <h2 style="margin-bottom: 8px; color: var(--text-primary);"><i class="fas fa-palette"></i> <?= __('settings_tab_branding') ?></h2>
+            <h2 style="margin-bottom: 8px; color: var(--text-primary);"><i class="fas fa-palette" aria-hidden="true"></i> <?= __('settings_tab_branding') ?></h2>
             <p style="color: var(--text-muted); font-size: 14px; margin-bottom: 24px;"><?= __('settings_branding_intro') ?></p>
             <form method="post">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
@@ -449,8 +449,8 @@ $adminBase = '';
                 <div class="card" id="brandPreview" style="margin-top: 8px;">
                     <h3><?= __('settings_brand_preview') ?></h3>
                     <div style="display:flex;flex-wrap:wrap;gap:12px;align-items:center;margin-top:14px;">
-                        <span class="brand-mark" style="width:38px;height:38px;"><i class="fas fa-wifi"></i></span>
-                        <button type="button" class="btn btn-primary"><i class="fas fa-ticket"></i> <?= __('voucher_create_btn') ?></button>
+                        <span class="brand-mark" style="width:38px;height:38px;"><i class="fas fa-wifi" aria-hidden="true"></i></span>
+                        <button type="button" class="btn btn-primary"><i class="fas fa-ticket" aria-hidden="true"></i> <?= __('voucher_create_btn') ?></button>
                         <button type="button" class="btn btn-secondary"><?= __('btn_cancel') ?></button>
                         <span class="badge badge-success"><?= __('status_valid') ?></span>
                         <span class="chip"><?= __('nav_vouchers') ?></span>
@@ -458,13 +458,13 @@ $adminBase = '';
                     </div>
                 </div>
 
-                <button type="submit" name="save_settings" class="btn btn-primary" style="margin-top:16px;"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                <button type="submit" name="save_settings" class="btn btn-primary" style="margin-top:16px;"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
             </form>
         </div>
 
         <!-- Login-Seite -->
         <div id="tab-login" class="tab-content">
-            <h2 style="margin-bottom: 8px; color: var(--text-primary);"><i class="fas fa-right-to-bracket"></i> <?= __('settings_tab_login') ?></h2>
+            <h2 style="margin-bottom: 8px; color: var(--text-primary);"><i class="fas fa-right-to-bracket" aria-hidden="true"></i> <?= __('settings_tab_login') ?></h2>
             <p style="color: var(--text-muted); font-size: 14px; margin-bottom: 24px;"><?= __('settings_login_intro') ?></p>
             <form method="post" enctype="multipart/form-data">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
@@ -532,9 +532,9 @@ $adminBase = '';
                 </div>
 
                 <div style="display:flex;gap:10px;flex-wrap:wrap;margin-top:16px;">
-                    <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                    <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
                     <a href="../login.php?preview=1" target="_blank" rel="noopener" class="btn btn-secondary">
-                        <i class="fas fa-arrow-up-right-from-square"></i> <?= __('settings_login_preview') ?>
+                        <i class="fas fa-arrow-up-right-from-square" aria-hidden="true"></i> <?= __('settings_login_preview') ?>
                     </a>
                 </div>
             </form>
@@ -542,24 +542,24 @@ $adminBase = '';
 
         <!-- Cron-Sync -->
         <div id="tab-cron" class="tab-content">
-            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-clock"></i> <?= __('settings_tab_cron') ?></h2>
+            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-clock" aria-hidden="true"></i> <?= __('settings_tab_cron') ?></h2>
             <div class="info-box">
-                <h4><i class="fas fa-info-circle"></i> <?= __('settings_cron_what') ?></h4>
+                <h4><i class="fas fa-info-circle" aria-hidden="true"></i> <?= __('settings_cron_what') ?></h4>
                 <p>Der Cron-Job synchronisiert automatisch alle Voucher von Ihren UniFi Controllern in die lokale Datenbank.</p>
             </div>
             <hr class="section-divider">
             <?php if (empty($cs['cron_token'])): ?>
-                <p style="color: var(--text-muted); margin-bottom: 15px;"><i class="fas fa-exclamation-triangle" style="color: var(--warning);"></i> Kein Token konfiguriert.</p>
+                <p style="color: var(--text-muted); margin-bottom: 15px;"><i class="fas fa-exclamation-triangle" style="color: var(--warning);" aria-hidden="true"></i> Kein Token konfiguriert.</p>
                 <form method="post">
                     <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
-                    <button type="submit" name="generate_cron_token" class="btn btn-primary"><i class="fas fa-key"></i> Token generieren</button>
+                    <button type="submit" name="generate_cron_token" class="btn btn-primary"><i class="fas fa-key" aria-hidden="true"></i> Token generieren</button>
                 </form>
             <?php else: ?>
                 <div class="token-box" style="margin-bottom: 15px;"><?= htmlspecialchars($cs['cron_token']) ?></div>
                 <div style="display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 20px;">
-                    <button onclick="copyToClipboard('<?= htmlspecialchars($cs['cron_token']) ?>')" class="btn btn-secondary"><i class="fas fa-copy"></i> Kopieren</button>
-                    <form method="post" style="display:inline;"><input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>"><button type="submit" name="generate_cron_token" class="btn btn-secondary"><i class="fas fa-sync"></i> Neu generieren</button></form>
-                    <form method="post" style="display:inline;" onsubmit="return confirm('<?= __('js_confirm_delete_token') ?>');"><input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>"><button type="submit" name="delete_cron_token" class="btn btn-secondary" style="color: var(--danger);"><i class="fas fa-trash"></i> Löschen</button></form>
+                    <button onclick="copyToClipboard('<?= htmlspecialchars($cs['cron_token']) ?>')" class="btn btn-secondary"><i class="fas fa-copy" aria-hidden="true"></i> Kopieren</button>
+                    <form method="post" style="display:inline;"><input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>"><button type="submit" name="generate_cron_token" class="btn btn-secondary"><i class="fas fa-sync" aria-hidden="true"></i> Neu generieren</button></form>
+                    <form method="post" style="display:inline;" onsubmit="return confirm('<?= __('js_confirm_delete_token') ?>');"><input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>"><button type="submit" name="delete_cron_token" class="btn btn-secondary" style="color: var(--danger);"><i class="fas fa-trash" aria-hidden="true"></i> Löschen</button></form>
                 </div>
             <?php endif; ?>
             <?php
@@ -569,7 +569,7 @@ $adminBase = '';
                 <label>Cron-URL</label>
                 <div style="display:flex;gap:10px;">
                     <input type="text" id="cronUrl" value="<?= htmlspecialchars($cronUrl) ?>" readonly>
-                    <button onclick="copyToClipboard(document.getElementById('cronUrl').value)" class="btn btn-secondary"><i class="fas fa-copy"></i></button>
+                    <button onclick="copyToClipboard(document.getElementById('cronUrl').value)" class="btn btn-secondary"><i class="fas fa-copy" aria-hidden="true"></i></button>
                 </div>
             </div>
             <div class="placeholder-info" style="background: var(--bg-hover); border-color: var(--border-color);">
@@ -580,7 +580,7 @@ $adminBase = '';
             </div>
             <?php if ($cs['cron_token']): ?>
             <div style="margin-top: 20px;">
-                <button onclick="testCronJob()" class="btn btn-primary" id="testCronBtn"><i class="fas fa-play"></i> Jetzt ausführen</button>
+                <button onclick="testCronJob()" class="btn btn-primary" id="testCronBtn"><i class="fas fa-play" aria-hidden="true"></i> Jetzt ausführen</button>
                 <span id="testCronResult" style="margin-left: 15px;"></span>
             </div>
             <?php endif; ?>
@@ -589,9 +589,9 @@ $adminBase = '';
 
         <!-- M365 -->
         <div id="tab-m365" class="tab-content">
-            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fab fa-microsoft"></i> Microsoft 365</h2>
+            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fab fa-microsoft" aria-hidden="true"></i> Microsoft 365</h2>
             <div class="info-box">
-                <h4><i class="fas fa-info-circle"></i> Azure AD App</h4>
+                <h4><i class="fas fa-info-circle" aria-hidden="true"></i> Azure AD App</h4>
                 <p>Redirect URI: <strong><?= $protocol . '://' . $host . $scriptPath ?>/m365_callback.php</strong></p>
             </div>
             <form method="post">
@@ -600,13 +600,13 @@ $adminBase = '';
                 <div class="form-group"><label>Client ID</label><input type="text" name="m365_client_id" value="<?= htmlspecialchars($cs['m365_client_id']) ?>"></div>
                 <div class="form-group"><label>Client Secret</label><input type="password" name="m365_client_secret" value="<?= htmlspecialchars($cs['m365_client_secret']) ?>"></div>
                 <div class="form-group"><label>Tenant ID</label><input type="text" name="m365_tenant_id" value="<?= htmlspecialchars($cs['m365_tenant_id']) ?>"></div>
-                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
             </form>
         </div>
 
         <!-- SMTP -->
         <div id="tab-smtp" class="tab-content">
-            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-envelope"></i> SMTP</h2>
+            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-envelope" aria-hidden="true"></i> SMTP</h2>
             <form method="post">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
                 <input type="hidden" name="form_type" value="smtp">
@@ -624,20 +624,20 @@ $adminBase = '';
                     <div class="form-group"><label>Absender E-Mail</label><input type="email" name="smtp_from_email" value="<?= htmlspecialchars($cs['smtp_from_email']) ?>"></div>
                     <div class="form-group"><label><?= __('settings_smtp_from_name') ?></label><input type="text" name="smtp_from_name" value="<?= htmlspecialchars($cs['smtp_from_name']) ?>"></div>
                 </div>
-                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
             </form>
             <hr class="section-divider">
             <h3 style="margin-bottom:15px; color: var(--text-primary);">SMTP testen</h3>
             <div style="display:flex;gap:10px;align-items:flex-end;">
                 <div style="flex:1;"><label>Test-E-Mail senden an</label><input type="email" id="smtpTestEmail" placeholder="empfaenger@example.com" style="margin-top:6px;"></div>
-                <button onclick="testSmtp()" class="btn btn-secondary" id="smtpTestBtn"><i class="fas fa-paper-plane"></i> <?= __('btn_test') ?></button>
+                <button onclick="testSmtp()" class="btn btn-secondary" id="smtpTestBtn"><i class="fas fa-paper-plane" aria-hidden="true"></i> <?= __('btn_test') ?></button>
             </div>
             <span id="smtpTestResult" style="display:block;margin-top:10px;font-size:13px;"></span>
         </div>
 
         <!-- E-Mail Templates -->
         <div id="tab-templates_email" class="tab-content">
-            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-file-alt"></i> E-Mail Templates</h2>
+            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-file-alt" aria-hidden="true"></i> E-Mail Templates</h2>
             <form method="post">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
                 <input type="hidden" name="form_type" value="templates">
@@ -652,18 +652,18 @@ $adminBase = '';
                 <div class="placeholder-info"><h4>Platzhalter:</h4><div class="placeholder-list"><code>{USER_NAME}</code><code>{CHANGES}</code><code>{APP_TITLE}</code><code>{SYSTEM_URL}</code></div></div>
                 <div class="form-group"><label>Betreff</label><input type="text" name="email_user_notification_subject" value="<?= htmlspecialchars($cs['email_user_notification_subject']) ?>"></div>
                 <div class="form-group"><label>E-Mail Text</label><textarea name="email_user_notification_body" class="tinymce-editor"><?= htmlspecialchars($cs['email_user_notification_body']) ?></textarea></div>
-                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
             </form>
         </div>
 
         <!-- System -->
         <div id="tab-system" class="tab-content">
-            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-cogs"></i> System & Erweitert</h2>
+            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-cogs" aria-hidden="true"></i> System & Erweitert</h2>
             <form method="post">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
                 <input type="hidden" name="form_type" value="system">
                 <div class="info-box">
-                    <h4><i class="fas fa-info-circle"></i> WYSIWYG-Editor</h4>
+                    <h4><i class="fas fa-info-circle" aria-hidden="true"></i> WYSIWYG-Editor</h4>
                     <p><?= __('settings_editor_hint') ?> <code>assets/vendor/</code> <?= __('settings_editor_hint2') ?></p>
                 </div>
 
@@ -671,7 +671,7 @@ $adminBase = '';
                 <h3 style="margin-bottom:15px; color: var(--text-primary);">Druck-Template</h3>
                 <div class="placeholder-info"><h4>Platzhalter:</h4><div class="placeholder-list"><code>{VOUCHER_CODE}</code><code>{EXPIRY_DATE}</code><code>{EXPIRY_TIME}</code><code>{SITE_NAME}</code><code>{MAX_USES}</code><code>{APP_TITLE}</code><code>{INSTRUCTIONS}</code></div></div>
                 <div class="form-group"><label><?= __('settings_print_template') ?></label><textarea name="print_template" class="tinymce-editor" style="min-height:250px;"><?= htmlspecialchars($cs['print_template']) ?></textarea></div>
-                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                <button type="submit" name="save_settings" class="btn btn-primary"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
             </form>
             <hr class="section-divider">
             <h3 style="margin-bottom:15px; color: var(--text-primary);">System-Information</h3>
@@ -684,13 +684,13 @@ $adminBase = '';
 
         <!-- Passwort -->
         <div id="tab-password" class="tab-content">
-            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-key"></i> <?= __('settings_tab_password') ?></h2>
+            <h2 style="margin-bottom: 20px; color: var(--text-primary);"><i class="fas fa-key" aria-hidden="true"></i> <?= __('settings_tab_password') ?></h2>
             <form method="post" style="max-width:500px;">
                 <input type="hidden" name="csrf_token" value="<?= $auth->getCsrfToken() ?>">
                 <div class="form-group"><label><?= __('settings_pw_current') ?></label><input type="password" name="current_password" required></div>
                 <div class="form-group"><label><?= __('settings_pw_new') ?></label><input type="password" name="new_password" required minlength="8"><div class="help-text"><?= __('settings_pw_minlength') ?></div></div>
                 <div class="form-group"><label><?= __('settings_pw_confirm') ?></label><input type="password" name="confirm_password" required></div>
-                <button type="submit" name="change_password" class="btn btn-primary"><i class="fas fa-lock"></i> <?= __('settings_tab_password') ?></button>
+                <button type="submit" name="change_password" class="btn btn-primary"><i class="fas fa-lock" aria-hidden="true"></i> <?= __('settings_tab_password') ?></button>
             </form>
         </div>
     </div>
@@ -763,7 +763,7 @@ async function testSmtp() {
     const result = document.getElementById('smtpTestResult');
     if (!email) { result.textContent = '<?= __('js_enter_email') ?>'; return; }
     btn.disabled = true;
-    btn.innerHTML = '<i class="fas fa-spinner fa-spin"></i>';
+    btn.innerHTML = '<i class="fas fa-spinner fa-spin" aria-hidden="true"></i>';
     const fd = new FormData();
     fd.append('ajax_smtp_test', '1');
     fd.append('csrf_token', '<?= $auth->getCsrfToken() ?>');
@@ -773,26 +773,26 @@ async function testSmtp() {
     result.textContent = data.message;
     result.style.color = data.success ? 'var(--success)' : 'var(--danger)';
     btn.disabled = false;
-    btn.innerHTML = '<i class="fas fa-paper-plane"></i> Testen';
+    btn.innerHTML = '<i class="fas fa-paper-plane" aria-hidden="true"></i> Testen';
 }
 
 async function testCronJob() {
     const btn = document.getElementById('testCronBtn');
     const result = document.getElementById('testCronResult');
     btn.disabled = true;
-    btn.innerHTML = '<i class="fas fa-spinner fa-spin"></i> <?= __('js_running') ?>';
+    btn.innerHTML = '<i class="fas fa-spinner fa-spin" aria-hidden="true"></i> <?= __('js_running') ?>';
     try {
         const res = await fetch('../cron_sync.php?token=<?= htmlspecialchars($cs['cron_token']) ?>');
         const data = await res.json();
         result.innerHTML = data.success
-            ? `<span style="color:var(--success)"><i class="fas fa-check-circle"></i> ${data.message}</span>`
-            : `<span style="color:var(--danger)"><i class="fas fa-times-circle"></i> ${data.message}</span>`;
+            ? `<span style="color:var(--success)"><i class="fas fa-check-circle" aria-hidden="true"></i> ${data.message}</span>`
+            : `<span style="color:var(--danger)"><i class="fas fa-times-circle" aria-hidden="true"></i> ${data.message}</span>`;
         if (data.success) showToast('success', 'Cron ausgeführt', data.message);
     } catch (e) {
         result.innerHTML = `<span style="color:var(--danger)"><?= __('js_error') ?>: ${e.message}</span>`;
     }
     btn.disabled = false;
-    btn.innerHTML = '<i class="fas fa-play"></i> <?= __('js_run_now') ?>';
+    btn.innerHTML = '<i class="fas fa-play" aria-hidden="true"></i> <?= __('js_run_now') ?>';
 }
 
 function initTinyMCE() {
diff --git a/admin/sites.php b/admin/sites.php
index 18afe47..23b0e14 100644
--- a/admin/sites.php
+++ b/admin/sites.php
@@ -105,20 +105,20 @@ $currentPage = 'sites';
 <div class="page-header">
     <h1 class="page-title"><?= __('sites_title') ?></h1>
     <button onclick="openModal()" class="btn btn-primary">
-        <i class="fas fa-plus"></i> <?= __('sites_add') ?>
+        <i class="fas fa-plus" aria-hidden="true"></i> <?= __('sites_add') ?>
     </button>
 </div>
 
 <?php if ($error): ?>
-    <div class="alert alert-error"><i class="fas fa-exclamation-circle"></i> <?= htmlspecialchars($error) ?></div>
+    <div class="alert alert-error"><i class="fas fa-exclamation-circle" aria-hidden="true"></i> <?= htmlspecialchars($error) ?></div>
 <?php endif; ?>
 <?php if ($success): ?>
-    <div class="alert alert-success"><i class="fas fa-check-circle"></i> <?= htmlspecialchars($success) ?></div>
+    <div class="alert alert-success"><i class="fas fa-check-circle" aria-hidden="true"></i> <?= htmlspecialchars($success) ?></div>
 <?php endif; ?>
 
 <?php if (empty($sites)): ?>
 <div class="empty-card">
-    <i class="fas fa-map-marker-alt" style="font-size:48px;margin-bottom:20px;opacity:.3;display:block;"></i>
+    <i class="fas fa-map-marker-alt" style="font-size:48px;margin-bottom:20px;opacity:.3;display:block;" aria-hidden="true"></i>
     <p><?= __('sites_none') ?></p>
 </div>
 <?php else: ?>
@@ -132,43 +132,43 @@ $currentPage = 'sites';
             </div>
             <div>
                 <?php if ($site['is_active']): ?>
-                    <span class="badge badge-success"><i class="fas fa-check"></i> <?= __('status_active') ?></span>
+                    <span class="badge badge-success"><i class="fas fa-check" aria-hidden="true"></i> <?= __('status_active') ?></span>
                 <?php else: ?>
-                    <span class="badge badge-warning"><i class="fas fa-pause"></i> <?= __('status_inactive') ?></span>
+                    <span class="badge badge-warning"><i class="fas fa-pause" aria-hidden="true"></i> <?= __('status_inactive') ?></span>
                 <?php endif; ?>
                 <?php if ($site['public_access']): ?>
-                    <span class="badge badge-info"><i class="fas fa-globe"></i> <?= __('status_public') ?></span>
+                    <span class="badge badge-info"><i class="fas fa-globe" aria-hidden="true"></i> <?= __('status_public') ?></span>
                 <?php endif; ?>
             </div>
         </div>
         <div class="site-info">
             <div class="site-info-item">
-                <i class="fas fa-server" style="color:var(--accent);width:16px;"></i>
+                <i class="fas fa-server" style="color:var(--accent);width:16px;" aria-hidden="true"></i>
                 <span style="word-break:break-all;"><?= htmlspecialchars($site['unifi_controller_url']) ?></span>
             </div>
             <div class="site-info-item">
-                <i class="fas fa-user" style="color:var(--accent);width:16px;"></i>
+                <i class="fas fa-user" style="color:var(--accent);width:16px;" aria-hidden="true"></i>
                 <span><?= htmlspecialchars($site['unifi_username']) ?></span>
             </div>
             <div class="site-info-item">
-                <i class="fas fa-clock" style="color:var(--text-muted);width:16px;"></i>
+                <i class="fas fa-clock" style="color:var(--text-muted);width:16px;" aria-hidden="true"></i>
                 <span style="color:var(--text-muted);"><?= date('d.m.Y', strtotime($site['created_at'])) ?></span>
             </div>
         </div>
         <div class="site-actions">
             <button onclick="openEditModal(<?= $site['id'] ?>, '<?= htmlspecialchars($site['name'], ENT_QUOTES) ?>', '<?= htmlspecialchars($site['site_id'], ENT_QUOTES) ?>', '<?= htmlspecialchars($site['unifi_controller_url'], ENT_QUOTES) ?>', '<?= htmlspecialchars($site['unifi_username'], ENT_QUOTES) ?>', <?= $site['public_access'] ?>)"
                     class="btn btn-secondary btn-sm">
-                <i class="fas fa-edit"></i> <?= __('btn_edit') ?>
+                <i class="fas fa-edit" aria-hidden="true"></i> <?= __('btn_edit') ?>
             </button>
             <a href="?toggle=<?= $site['id'] ?>&token=<?= $auth->getCsrfToken() ?>"
                class="btn btn-secondary btn-sm">
-                <i class="fas fa-<?= $site['is_active'] ? 'pause' : 'play' ?>"></i>
+                <i class="fas fa-<?= $site['is_active'] ? 'pause' : 'play' ?>" aria-hidden="true"></i>
                 <?= $site['is_active'] ? __('sites_deactivate') : __('sites_activate') ?>
             </a>
             <a href="?delete=<?= $site['id'] ?>&token=<?= $auth->getCsrfToken() ?>"
                class="btn btn-danger-soft btn-sm"
                onclick="return confirm('<?= __('js_confirm_delete_site') ?>')">
-                <i class="fas fa-trash"></i>
+                <i class="fas fa-trash" aria-hidden="true"></i>
             </a>
         </div>
     </div>
@@ -219,7 +219,7 @@ $currentPage = 'sites';
                 </div>
                 <div style="display:flex;gap:10px;margin-top:20px;">
                     <button type="submit" class="btn btn-primary" style="flex:1;" id="addSiteSubmitBtn">
-                        <i class="fas fa-save"></i> <?= __('sites_add') ?>
+                        <i class="fas fa-save" aria-hidden="true"></i> <?= __('sites_add') ?>
                     </button>
                     <button type="button" onclick="closeModal('addSiteModal')" class="btn btn-secondary"><?= __('btn_cancel') ?></button>
                 </div>
@@ -269,7 +269,7 @@ $currentPage = 'sites';
                 </div>
                 <div style="display:flex;gap:10px;margin-top:20px;">
                     <button type="submit" class="btn btn-primary" style="flex:1;" id="editSiteSubmitBtn">
-                        <i class="fas fa-save"></i> <?= __('btn_save') ?>
+                        <i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?>
                     </button>
                     <button type="button" onclick="closeModal('editSiteModal')" class="btn btn-secondary"><?= __('btn_cancel') ?></button>
                 </div>
@@ -278,7 +278,7 @@ $currentPage = 'sites';
     </div>
 </div>
 
-<div id="toast-container"></div>
+<div id="toast-container" role="status" aria-live="polite"></div>
 <script src="../assets/global.js"></script>
 <script>
 function openModal() { document.getElementById('addSiteModal').classList.add('active'); }
@@ -298,12 +298,12 @@ function openEditModal(id, name, siteIdStr, controllerUrl, username, publicAcces
 document.getElementById('addSiteForm').addEventListener('submit', function() {
     const btn = document.getElementById('addSiteSubmitBtn');
     btn.disabled = true;
-    btn.innerHTML = '<i class="fas fa-spinner fa-spin"></i> <?= addslashes(__('sites_testing')) ?>';
+    btn.innerHTML = '<i class="fas fa-spinner fa-spin" aria-hidden="true"></i> <?= addslashes(__('sites_testing')) ?>';
 });
 document.getElementById('editSiteForm').addEventListener('submit', function() {
     const btn = document.getElementById('editSiteSubmitBtn');
     btn.disabled = true;
-    btn.innerHTML = '<i class="fas fa-spinner fa-spin"></i> <?= addslashes(__('sites_testing')) ?>';
+    btn.innerHTML = '<i class="fas fa-spinner fa-spin" aria-hidden="true"></i> <?= addslashes(__('sites_testing')) ?>';
 });
 
 ['addSiteModal','editSiteModal'].forEach(id => {
diff --git a/admin/templates.php b/admin/templates.php
index c7c46e2..292675d 100644
--- a/admin/templates.php
+++ b/admin/templates.php
@@ -107,15 +107,15 @@ $adminBase   = '';
             <p class="page-subtitle"><?= __('templates_subtitle') ?></p>
         </div>
         <button onclick="openAddModal()" class="btn btn-primary">
-            <i class="fas fa-plus"></i> <?= __('templates_add') ?>
+            <i class="fas fa-plus" aria-hidden="true"></i> <?= __('templates_add') ?>
         </button>
     </div>
 
     <?php if ($error): ?>
-        <div class="alert alert-error"><i class="fas fa-exclamation-circle"></i> <?= htmlspecialchars($error) ?></div>
+        <div class="alert alert-error"><i class="fas fa-exclamation-circle" aria-hidden="true"></i> <?= htmlspecialchars($error) ?></div>
     <?php endif; ?>
     <?php if ($success): ?>
-        <div class="alert alert-success"><i class="fas fa-check-circle"></i> <?= htmlspecialchars($success) ?></div>
+        <div class="alert alert-success"><i class="fas fa-check-circle" aria-hidden="true"></i> <?= htmlspecialchars($success) ?></div>
     <?php endif; ?>
 
     <div class="card">
@@ -125,15 +125,15 @@ $adminBase   = '';
         </div>
         <?php if (empty($templates)): ?>
             <div class="empty-state">
-                <i class="fas fa-layer-group"></i>
+                <i class="fas fa-layer-group" aria-hidden="true"></i>
                 <p style="font-size: 15px; margin-bottom: 8px;"><?= __('templates_none') ?></p>
                 <p style="font-size: 13px;"><?= __('templates_add_hint') ?></p>
-                <button onclick="openAddModal()" class="btn btn-primary" style="margin-top: 20px;"><i class="fas fa-plus"></i> <?= __('templates_add') ?></button>
+                <button onclick="openAddModal()" class="btn btn-primary" style="margin-top: 20px;"><i class="fas fa-plus" aria-hidden="true"></i> <?= __('templates_add') ?></button>
             </div>
         <?php else: ?>
             <div style="overflow-x: auto;">
                 <div class="table-container">
-                <table class="table">
+                <table class="table table-stack">
                     <thead>
                         <tr>
                             <th><?= __('templates_name') ?></th>
@@ -147,11 +147,11 @@ $adminBase   = '';
                     <tbody>
                         <?php foreach ($templates as $t): ?>
                         <tr>
-                            <td><strong><?= htmlspecialchars($t['name']) ?></strong></td>
-                            <td>
-                                <span class="duration-badge"><i class="fas fa-mobile-alt"></i> <?= (int)$t['max_uses'] ?></span>
+                            <td data-label="<?= __('templates_name') ?>"><strong><?= htmlspecialchars($t['name']) ?></strong></td>
+                            <td data-label="<?= __('templates_devices') ?>">
+                                <span class="duration-badge"><i class="fas fa-mobile-alt" aria-hidden="true"></i> <?= (int)$t['max_uses'] ?></span>
                             </td>
-                            <td>
+                            <td data-label="<?= __('templates_duration') ?>">
                                 <?php
                                 $m = (int)$t['expire_minutes'];
                                 if ($m >= 1440 && $m % 1440 === 0) {
@@ -162,22 +162,22 @@ $adminBase   = '';
                                     $durLabel = $m . ' Min.';
                                 }
                                 ?>
-                                <span class="duration-badge"><i class="fas fa-clock"></i> <?= $durLabel ?></span>
+                                <span class="duration-badge"><i class="fas fa-clock" aria-hidden="true"></i> <?= $durLabel ?></span>
                             </td>
-                            <td style="color: var(--text-secondary);"><?= htmlspecialchars($t['description'] ?? '-') ?></td>
-                            <td>
+                            <td data-label="<?= __('templates_desc') ?>" style="color: var(--text-secondary);"><?= htmlspecialchars($t['description'] ?? '-') ?></td>
+                            <td data-label="<?= __('label_status') ?>">
                                 <?php if ($t['is_active']): ?>
                                     <span class="badge badge-success"><?= __('status_active') ?></span>
                                 <?php else: ?>
                                     <span class="badge badge-secondary"><?= __('status_inactive') ?></span>
                                 <?php endif; ?>
                             </td>
-                            <td>
+                            <td data-label="<?= __('label_actions') ?>">
                                 <button onclick="openEditModal(<?= $t['id'] ?>, '<?= htmlspecialchars($t['name'], ENT_QUOTES) ?>', <?= (int)$t['max_uses'] ?>, <?= (int)$t['expire_minutes'] ?>, '<?= htmlspecialchars($t['description'] ?? '', ENT_QUOTES) ?>', <?= (int)$t['is_active'] ?>, <?= (int)($t['qos_rate_max_down'] ?? 0) ?>, <?= (int)($t['qos_rate_max_up'] ?? 0) ?>, <?= (int)($t['qos_usage_quota'] ?? 0) ?>)"
-                                        class="btn btn-secondary btn-small"><i class="fas fa-edit"></i></button>
+                                        class="btn btn-secondary btn-small"><i class="fas fa-edit" aria-hidden="true"></i></button>
                                 <a href="?delete=<?= $t['id'] ?>&token=<?= $auth->getCsrfToken() ?>"
                                    onclick="return confirm('<?= __('js_confirm_delete_template') ?>')"
-                                   class="btn btn-danger-soft btn-small"><i class="fas fa-trash"></i></a>
+                                   class="btn btn-danger-soft btn-small"><i class="fas fa-trash" aria-hidden="true"></i></a>
                             </td>
                         </tr>
                         <?php endforeach; ?>
@@ -194,7 +194,7 @@ $adminBase   = '';
 <div id="addModal" class="modal">
     <div class="modal-content">
         <div class="modal-header">
-            <h2 class="modal-title"><i class="fas fa-plus-circle" style="color: var(--accent);"></i> <?= __('templates_add') ?></h2>
+            <h2 class="modal-title"><i class="fas fa-plus-circle" style="color: var(--accent);" aria-hidden="true"></i> <?= __('templates_add') ?></h2>
             <button class="modal-close" onclick="closeModal('addModal')">&times;</button>
         </div>
         <div class="modal-body">
@@ -220,7 +220,7 @@ $adminBase   = '';
                     <div class="form-group"><label>Datenlimit (MB)</label><input type="number" name="qos_usage_quota" min="0" placeholder="0 = unbegrenzt"></div>
                 </div>
                 <div style="display:flex;gap:10px;margin-top:20px;">
-                    <button type="submit" name="add_template" class="btn btn-primary" style="flex:1;"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                    <button type="submit" name="add_template" class="btn btn-primary" style="flex:1;"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
                     <button type="button" onclick="closeModal('addModal')" class="btn btn-secondary"><?= __('btn_cancel') ?></button>
                 </div>
             </form>
@@ -232,7 +232,7 @@ $adminBase   = '';
 <div id="editModal" class="modal">
     <div class="modal-content">
         <div class="modal-header">
-            <h2 class="modal-title"><i class="fas fa-edit" style="color: var(--accent);"></i> <?= __('templates_edit') ?></h2>
+            <h2 class="modal-title"><i class="fas fa-edit" style="color: var(--accent);" aria-hidden="true"></i> <?= __('templates_edit') ?></h2>
             <button class="modal-close" onclick="closeModal('editModal')">&times;</button>
         </div>
         <div class="modal-body">
@@ -261,7 +261,7 @@ $adminBase   = '';
                     <label for="editActive" style="margin:0;"><?= __('status_active') ?></label>
                 </div>
                 <div style="display:flex;gap:10px;">
-                    <button type="submit" name="edit_template" class="btn btn-primary" style="flex:1;"><i class="fas fa-save"></i> <?= __('btn_save') ?></button>
+                    <button type="submit" name="edit_template" class="btn btn-primary" style="flex:1;"><i class="fas fa-save" aria-hidden="true"></i> <?= __('btn_save') ?></button>
                     <button type="button" onclick="closeModal('editModal')" class="btn btn-secondary"><?= __('btn_cancel') ?></button>
                 </div>
             </form>
diff --git a/admin/users.php b/admin/users.php
index 90e83b2..557bb55 100644
--- a/admin/users.php
+++ b/admin/users.php
@@ -175,26 +175,26 @@ $currentPage = 'users';
 <div class="page-header">
     <h1 class="page-title"><?= __('users_title') ?></h1>
     <button onclick="openModal()" class="btn btn-primary">
-        <i class="fas fa-plus"></i> <?= __('users_add') ?>
+        <i class="fas fa-plus" aria-hidden="true"></i> <?= __('users_add') ?>
     </button>
 </div>
 
 <?php if ($error): ?>
-    <div class="alert alert-error"><i class="fas fa-exclamation-circle"></i> <?= htmlspecialchars($error) ?></div>
+    <div class="alert alert-error"><i class="fas fa-exclamation-circle" aria-hidden="true"></i> <?= htmlspecialchars($error) ?></div>
 <?php endif; ?>
 <?php if ($success): ?>
-    <div class="alert alert-success"><i class="fas fa-check-circle"></i> <?= htmlspecialchars($success) ?></div>
+    <div class="alert alert-success"><i class="fas fa-check-circle" aria-hidden="true"></i> <?= htmlspecialchars($success) ?></div>
 <?php endif; ?>
 
 <div class="card">
     <div class="card-header"><h2 class="card-title"><?= __('users_all') ?></h2></div>
     <div class="card-body" style="padding:0;">
         <?php if (empty($users)): ?>
-            <div class="empty-state"><i class="fas fa-users"></i><p><?= __('users_none_found') ?></p></div>
+            <div class="empty-state"><i class="fas fa-users" aria-hidden="true"></i><p><?= __('users_none_found') ?></p></div>
         <?php else: ?>
         <div style="overflow-x:auto;">
         <div class="table-container">
-        <table class="table">
+        <table class="table table-stack">
             <thead>
                 <tr>
                     <th><?= __('label_name') ?></th>
@@ -210,28 +210,28 @@ $currentPage = 'users';
                 <?php foreach ($users as $user): ?>
                 <?php $userSiteIds = array_column($userSiteAccess[$user['id']]??[], 'id'); ?>
                 <tr>
-                    <td>
+                    <td data-label="<?= __('label_name') ?>">
                         <strong><?= htmlspecialchars($user['name']) ?></strong>
                         <?php if ($user['id'] == $_SESSION['user_id']): ?>
                             <span class="badge badge-info"><?= __('users_you') ?></span>
                         <?php endif; ?>
                     </td>
-                    <td><?= htmlspecialchars($user['email']) ?></td>
-                    <td>
+                    <td data-label="<?= __('label_email') ?>"><?= htmlspecialchars($user['email']) ?></td>
+                    <td data-label="<?= __('label_role') ?>">
                         <?php if ($user['is_admin']): ?>
-                            <span class="badge badge-danger"><i class="fas fa-crown"></i> <?= __('status_admin') ?></span>
+                            <span class="badge badge-danger"><i class="fas fa-crown" aria-hidden="true"></i> <?= __('status_admin') ?></span>
                         <?php else: ?>
                             <span class="badge badge-info"><?= __('status_user') ?></span>
                         <?php endif; ?>
                     </td>
-                    <td>
+                    <td data-label="<?= __('label_status') ?>">
                         <?php if ($user['is_active']): ?>
-                            <span class="badge badge-success"><i class="fas fa-check"></i> <?= __('status_active') ?></span>
+                            <span class="badge badge-success"><i class="fas fa-check" aria-hidden="true"></i> <?= __('status_active') ?></span>
                         <?php else: ?>
-                            <span class="badge badge-warning"><i class="fas fa-pause"></i> <?= __('status_inactive') ?></span>
+                            <span class="badge badge-warning"><i class="fas fa-pause" aria-hidden="true"></i> <?= __('status_inactive') ?></span>
                         <?php endif; ?>
                     </td>
-                    <td>
+                    <td data-label="<?= __('users_site_access') ?>">
                         <?php if ($user['is_admin']): ?>
                             <em style="color:var(--text-muted);"><?= __('users_all_sites') ?></em>
                         <?php elseif (!empty($userSiteAccess[$user['id']])): ?>
@@ -242,7 +242,7 @@ $currentPage = 'users';
                             <em style="color:var(--text-muted);"><?= __('users_none') ?></em>
                         <?php endif; ?>
                     </td>
-                    <td style="font-size:13px;">
+                    <td data-label="<?= __('users_last_login') ?>" style="font-size:13px;">
                         <?php if ($user['last_login']): ?>
                             <?= date('d.m.Y H:i', strtotime($user['last_login'])) ?>
                         <?php else: ?>
@@ -253,31 +253,31 @@ $currentPage = 'users';
                         <div class="action-btns">
                             <button onclick="openEditModal(<?= $user['id'] ?>, '<?= htmlspecialchars($user['name'], ENT_QUOTES) ?>', <?= $user['is_admin'] ?>, [<?= implode(',', array_map('intval', $userSiteIds)) ?>])"
                                     class="btn btn-secondary btn-sm" title="<?= __('btn_edit') ?>">
-                                <i class="fas fa-edit"></i>
+                                <i class="fas fa-edit" aria-hidden="true"></i>
                             </button>
                             <?php if ($user['id'] != $_SESSION['user_id']): ?>
                                 <a href="?toggle=<?= $user['id'] ?>&token=<?= $auth->getCsrfToken() ?>"
                                    class="btn btn-secondary btn-sm" title="<?= $user['is_active'] ? __('sites_deactivate') : __('sites_activate') ?>">
-                                    <i class="fas fa-<?= $user['is_active'] ? 'pause' : 'play' ?>"></i>
+                                    <i class="fas fa-<?= $user['is_active'] ? 'pause' : 'play' ?>" aria-hidden="true"></i>
                                 </a>
                                 <?php if ($smtpEnabled && !empty($user['password_hash'])): ?>
                                 <a href="?send_reset=<?= $user['id'] ?>&token=<?= $auth->getCsrfToken() ?>"
                                    class="btn btn-warning btn-sm" title="<?= __('users_reset_pw') ?>"
                                    onclick="return confirm('Passwort-Reset-Link senden an <?= htmlspecialchars($user['email'], ENT_QUOTES) ?>?')">
-                                    <i class="fas fa-key"></i>
+                                    <i class="fas fa-key" aria-hidden="true"></i>
                                 </a>
                                 <?php endif; ?>
                                 <?php if (!empty($user['totp_enabled'])): ?>
                                 <a href="?reset_2fa=<?= $user['id'] ?>&token=<?= $auth->getCsrfToken() ?>"
                                    class="btn btn-secondary btn-sm" title="2FA zurücksetzen"
                                    onclick="return confirm('2FA für <?= htmlspecialchars($user['email'], ENT_QUOTES) ?> zurücksetzen?')">
-                                    <i class="fas fa-user-shield"></i>
+                                    <i class="fas fa-user-shield" aria-hidden="true"></i>
                                 </a>
                                 <?php endif; ?>
                                 <a href="?delete=<?= $user['id'] ?>&token=<?= $auth->getCsrfToken() ?>"
                                    class="btn btn-danger-soft btn-sm" title="<?= __('btn_delete') ?>"
                                    onclick="return confirm('<?= __('js_confirm_delete_user') ?>')">
-                                    <i class="fas fa-trash"></i>
+                                    <i class="fas fa-trash" aria-hidden="true"></i>
                                 </a>
                             <?php endif; ?>
                         </div>
@@ -342,7 +342,7 @@ $currentPage = 'users';
                 </div>
                 <div style="display:flex;gap:10px;margin-top:20px;">
                     <button type="submit" name="add_user" class="btn btn-primary" style="flex:1;">
-                        <i class="fas fa-save"></i> <?= __('users_save') ?>
+                        <i class="fas fa-save" aria-hidden="true"></i> <?= __('users_save') ?>
                     </button>
                     <button type="button" onclick="closeModal('addUserModal')" class="btn btn-secondary"><?= __('btn_cancel') ?></button>
                 </div>
@@ -386,7 +386,7 @@ $currentPage = 'users';
                 </div>
                 <div style="display:flex;gap:10px;margin-top:20px;">
                     <button type="submit" name="edit_user" class="btn btn-primary" style="flex:1;">
-                        <i class="fas fa-save"></i> <?= __('users_save_edit') ?>
+                        <i class="fas fa-save" aria-hidden="true"></i> <?= __('users_save_edit') ?>
                     </button>
                     <button type="button" onclick="closeModal('editUserModal')" class="btn btn-secondary"><?= __('btn_cancel') ?></button>
                 </div>
@@ -395,7 +395,7 @@ $currentPage = 'users';
     </div>
 </div>
 
-<div id="toast-container"></div>
+<div id="toast-container" role="status" aria-live="polite"></div>
 <script src="../assets/global.js"></script>
 <script>
 function openModal() { document.getElementById('addUserModal').classList.add('active'); }
diff --git a/admin/vouchers.php b/admin/vouchers.php
index 9b241ea..3c456eb 100644
--- a/admin/vouchers.php
+++ b/admin/vouchers.php
@@ -143,9 +143,9 @@ $currentPage  = 'vouchers';
 
 <?php if (empty($sites)): ?>
 <div class="no-sites-warning">
-    <i class="fas fa-triangle-exclamation" style="font-size:26px;margin-bottom:12px;display:block;"></i>
+    <i class="fas fa-triangle-exclamation" style="font-size:26px;margin-bottom:12px;display:block;" aria-hidden="true"></i>
     <h3><?= __('vouchers_no_sites') ?></h3>
-    <a href="sites.php" class="btn btn-primary" style="margin-top:20px;"><i class="fas fa-plus"></i> <?= __('nav_sites') ?></a>
+    <a href="sites.php" class="btn btn-primary" style="margin-top:20px;"><i class="fas fa-plus" aria-hidden="true"></i> <?= __('nav_sites') ?></a>
 </div>
 <?php else: ?>
 
@@ -168,7 +168,7 @@ $currentPage  = 'vouchers';
             </select>
             <input type="search" id="searchInput" class="search-bar" placeholder="<?= __('vouchers_search') ?>" oninput="filterAndRender()" style="display:none;">
             <button id="refreshBtn" class="btn btn-secondary" onclick="loadVouchers(true)" disabled>
-                <i class="fas fa-sync-alt"></i> <?= __('btn_refresh') ?>
+                <i class="fas fa-sync-alt" aria-hidden="true"></i> <?= __('btn_refresh') ?>
             </button>
         </div>
     </div>
@@ -187,12 +187,12 @@ $currentPage  = 'vouchers';
     <div class="card-header">
         <h2 class="card-title" id="voucherListTitle">Vouchers</h2>
         <a id="csvExportBtn" style="display:none;" class="btn btn-secondary btn-sm" href="#">
-            <i class="fas fa-download"></i> <?= __('btn_export_csv') ?>
+            <i class="fas fa-download" aria-hidden="true"></i> <?= __('btn_export_csv') ?>
         </a>
     </div>
     <div class="card-body" style="padding:0;">
         <div id="voucherContent">
-            <div class="empty-state"><i class="fas fa-ticket-alt"></i><p><?= __('vouchers_select_hint') ?></p></div>
+            <div class="empty-state"><i class="fas fa-ticket-alt" aria-hidden="true"></i><p><?= __('vouchers_select_hint') ?></p></div>
         </div>
     </div>
 </div>
@@ -200,10 +200,12 @@ $currentPage  = 'vouchers';
 
 </main>
 
-<div id="toast-container"></div>
+<div id="toast-container" role="status" aria-live="polite"></div>
 <script src="../assets/global.js"></script>
 <script>
 const csrfToken = '<?= $auth->getCsrfToken() ?>';
+// Datums- und Zeitformat folgen der gewaehlten Sprache
+const LOCALE = '<?= I18n::getLanguage() === 'en' ? 'en-GB' : 'de-DE' ?>';
 let currentSiteId = null;
 let allVouchers   = [];
 let currentFilter = 'all';
@@ -218,7 +220,7 @@ async function loadVouchers(syncFirst=false) {
     const searchInput = document.getElementById('searchInput');
 
     if (!siteId) {
-        document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-ticket-alt"></i><p><?= addslashes(__('vouchers_select_hint')) ?></p></div>`;
+        document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-ticket-alt" aria-hidden="true"></i><p><?= addslashes(__('vouchers_select_hint')) ?></p></div>`;
         document.getElementById('statsContainer').style.display = 'none';
         searchInput.style.display = 'none';
         refreshBtn.disabled = true;
@@ -227,9 +229,9 @@ async function loadVouchers(syncFirst=false) {
 
     currentSiteId = siteId;
     refreshBtn.disabled = false;
-    refreshBtn.innerHTML = `<i class="fas fa-spinner fa-spin"></i> ${syncFirst ? '<?= addslashes(__('btn_refresh')) ?>' : '<?= addslashes(__('btn_refresh')) ?>'}`;
+    refreshBtn.innerHTML = `<i class="fas fa-spinner fa-spin" aria-hidden="true"></i> ${syncFirst ? '<?= addslashes(__('btn_refresh')) ?>' : '<?= addslashes(__('btn_refresh')) ?>'}`;
 
-    document.getElementById('voucherContent').innerHTML = `<div class="loading"><i class="fas fa-spinner"></i><span>${syncFirst ? 'Synchronisiere...' : 'Lade...'}</span></div>`;
+    document.getElementById('voucherContent').innerHTML = `<div class="loading"><i class="fas fa-spinner" aria-hidden="true"></i><span>${syncFirst ? 'Synchronisiere...' : 'Lade...'}</span></div>`;
 
     try {
         const result = await fetch(`vouchers.php?ajax_get_vouchers=1&site_id=${siteId}${syncFirst?'&sync=1':''}`).then(r=>r.json());
@@ -247,15 +249,15 @@ async function loadVouchers(syncFirst=false) {
             csvBtn.href = `vouchers.php?export_csv=1&site_id=${siteId}&token=${csrfToken}`;
             if (syncFirst) showToast('success', '<?= addslashes(__('btn_refresh')) ?>', `${result.count} Vouchers geladen`);
         } else {
-            document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-exclamation-circle" style="color:var(--danger)"></i><p>${result.message}</p></div>`;
+            document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-exclamation-circle" style="color:var(--danger)" aria-hidden="true"></i><p>${result.message}</p></div>`;
             document.getElementById('statsContainer').style.display = 'none';
         }
     } catch(e) {
-        document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-exclamation-circle" style="color:var(--danger)"></i><p>Verbindungsfehler: ${e.message}</p></div>`;
+        document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-exclamation-circle" style="color:var(--danger)" aria-hidden="true"></i><p>Verbindungsfehler: ${e.message}</p></div>`;
         document.getElementById('statsContainer').style.display = 'none';
     }
     refreshBtn.disabled = false;
-    refreshBtn.innerHTML = '<i class="fas fa-sync-alt"></i> <?= addslashes(__('btn_refresh')) ?>';
+    refreshBtn.innerHTML = '<i class="fas fa-sync-alt" aria-hidden="true"></i> <?= addslashes(__('btn_refresh')) ?>';
 }
 
 function updateStats() {
@@ -293,7 +295,7 @@ function renderVouchers() {
     const pageVouchers = vouchers.slice((currentPage-1)*PAGE_SIZE, currentPage*PAGE_SIZE);
 
     if (vouchers.length === 0) {
-        document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-ticket-alt"></i><p><?= addslashes(__('vouchers_none')) ?></p></div>`;
+        document.getElementById('voucherContent').innerHTML = `<div class="empty-state"><i class="fas fa-ticket-alt" aria-hidden="true"></i><p><?= addslashes(__('vouchers_none')) ?></p></div>`;
         return;
     }
 
@@ -309,7 +311,7 @@ function renderVouchers() {
             <button class="filter-btn ${currentFilter==='expired'?'active':''}" data-filter="expired" onclick="setFilter('expired')"><?= __('vouchers_filter_expired') ?> (${expiredCnt})</button>
         </div>
     </div>
-    <div class="table-container"><table class="table">
+    <div class="table-container"><table class="table table-stack">
         <thead><tr>
             <th><?= __('label_created') ?></th>
             <th><?= __('label_code') ?></th>
@@ -330,21 +332,21 @@ function renderVouchers() {
         })() : '';
         const usagePct   = v.quota > 0 ? Math.min(100, (v.used/v.quota)*100) : 0;
         const statusBadge = v.status==='valid'
-            ? `<span class="badge badge-success"><i class="fas fa-check"></i> <?= __('status_valid') ?></span>`
+            ? `<span class="badge badge-success"><i class="fas fa-check" aria-hidden="true"></i> <?= __('status_valid') ?></span>`
             : v.status==='used'
-            ? `<span class="badge badge-warning"><i class="fas fa-user-check"></i> <?= __('status_used') ?></span>`
-            : `<span class="badge badge-danger"><i class="fas fa-times"></i> <?= __('status_expired') ?></span>`;
+            ? `<span class="badge badge-warning"><i class="fas fa-user-check" aria-hidden="true"></i> <?= __('status_used') ?></span>`
+            : `<span class="badge badge-danger"><i class="fas fa-times" aria-hidden="true"></i> <?= __('status_expired') ?></span>`;
 
         html += `<tr id="voucher-${v._id}">
-            <td><strong>${createDate.toLocaleDateString('de-DE')}</strong><br><small style="color:var(--text-muted)">${createDate.toLocaleTimeString('de-DE',{hour:'2-digit',minute:'2-digit'})}</small></td>
-            <td><code onclick="copyToClipboard('${escapeHtml(v.formatted_code||'')}','Kopiert!')" title="Kopieren" style="cursor:pointer">${escapeHtml(v.formatted_code||'')}</code></td>
-            <td class="voucher-note" title="${escapeHtml(v.note||'-')}">${escapeHtml(v.note||'-')}</td>
-            <td>${statusBadge}</td>
-            <td><div class="usage-info"><span>${v.used}/${v.quota>0?v.quota:'∞'}</span>${v.quota>0?`<div class="usage-bar"><div class="usage-bar-fill" style="width:${usagePct}%"></div></div>`:''}</div></td>
-            <td>${remaining?`<span style="color:var(--success)"><i class="fas fa-clock"></i> ${remaining}</span><br>`:''}<small style="color:var(--text-muted)">${v.duration} Min.</small></td>
-            <td style="white-space:nowrap;">
-                <button onclick="resendVoucher('${v._id}','${escapeHtml(v.formatted_code||'')}')" class="btn btn-secondary btn-sm" title="Per E-Mail senden"><i class="fas fa-envelope"></i></button>
-                <button onclick="deleteVoucher('${v._id}')" class="btn btn-danger-soft btn-sm" title="<?= __('btn_delete') ?>"><i class="fas fa-trash"></i></button>
+            <td data-label="<?= __('label_created') ?>"><strong>${createDate.toLocaleDateString(LOCALE)}</strong><br><small style="color:var(--text-muted)">${createDate.toLocaleTimeString(LOCALE,{hour:'2-digit',minute:'2-digit'})}</small></td>
+            <td data-label="<?= __('label_code') ?>"><code onclick="copyToClipboard('${escapeHtml(v.formatted_code||'')}','<?= __('js_copied') ?>')" title="<?= __('js_copy') ?>" style="cursor:pointer">${escapeHtml(v.formatted_code||'')}</code></td>
+            <td class="voucher-note" data-label="<?= __('label_note') ?>" title="${escapeHtml(v.note||'-')}">${escapeHtml(v.note||'-')}</td>
+            <td data-label="<?= __('label_status') ?>">${statusBadge}</td>
+            <td data-label="<?= __('label_usage') ?>"><div class="usage-info"><span>${v.used}/${v.quota>0?v.quota:'∞'}</span>${v.quota>0?`<div class="usage-bar"><div class="usage-bar-fill" style="width:${usagePct}%"></div></div>`:''}</div></td>
+            <td data-label="<?= __('label_expires') ?>">${remaining?`<span style="color:var(--success)"><i class="fas fa-clock" aria-hidden="true"></i> ${remaining}</span><br>`:''}<small style="color:var(--text-muted)">${v.duration} <?= __('label_minutes_short') ?></small></td>
+            <td data-label="<?= __('label_actions') ?>" style="white-space:nowrap;">
+                <button onclick="resendVoucher('${v._id}','${escapeHtml(v.formatted_code||'')}')" class="btn btn-secondary btn-sm" title="<?= __('vouchers_resend') ?>" aria-label="<?= __('vouchers_resend') ?>"><i class="fas fa-envelope" aria-hidden="true"></i></button>
+                <button onclick="deleteVoucher('${v._id}')" class="btn btn-danger-soft btn-sm" title="<?= __('btn_delete') ?>" aria-label="<?= __('btn_delete') ?>"><i class="fas fa-trash" aria-hidden="true"></i></button>
             </td>
         </tr>`;
     });
@@ -356,11 +358,11 @@ function renderVouchers() {
             <span style="font-size:13px;color:var(--text-muted);">${<?= json_encode(__('vouchers_page_of')) ?>
                 .replace('{current}',currentPage).replace('{total}',totalPages)} (${vouchers.length})</span>
             <div style="display:flex;gap:5px;">
-                <button class="btn btn-secondary btn-sm" onclick="setPage(${currentPage-1})" ${currentPage<=1?'disabled':''}><i class="fas fa-chevron-left"></i></button>`;
+                <button class="btn btn-secondary btn-sm" onclick="setPage(${currentPage-1})" ${currentPage<=1?'disabled':''}><i class="fas fa-chevron-left" aria-hidden="true"></i></button>`;
         for (let p=Math.max(1,currentPage-2); p<=Math.min(totalPages,currentPage+2); p++) {
             html += `<button class="btn btn-sm ${p===currentPage?'btn-primary':'btn-secondary'}" onclick="setPage(${p})">${p}</button>`;
         }
-        html += `<button class="btn btn-secondary btn-sm" onclick="setPage(${currentPage+1})" ${currentPage>=totalPages?'disabled':''}><i class="fas fa-chevron-right"></i></button>
+        html += `<button class="btn btn-secondary btn-sm" onclick="setPage(${currentPage+1})" ${currentPage>=totalPages?'disabled':''}><i class="fas fa-chevron-right" aria-hidden="true"></i></button>
             </div></div>`;
     }
 
diff --git a/assets/global.css b/assets/global.css
index 7ef44d6..7657f72 100644
--- a/assets/global.css
+++ b/assets/global.css
@@ -27,7 +27,7 @@
     /* Text */
     --text-primary:   #101625;
     --text-secondary: #525c6e;
-    --text-muted:     #8a93a3;
+    --text-muted:     #6b7280;
     --text-inverse:   #ffffff;
 
     /* Linien */
@@ -107,7 +107,7 @@
 
     --text-primary:   #e9ecf3;
     --text-secondary: #a2abbd;
-    --text-muted:     #6f7889;
+    --text-muted:     #8a93a6;
     --text-inverse:   #0a0c11;
 
     --border-color:   #232838;
@@ -1531,6 +1531,67 @@ input.search-bar, .site-selector .search-bar { min-width: 240px; width: auto; fl
 .row3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
 @media (max-width: 720px) { .row, .row3 { grid-template-columns: 1fr; } }
 
+/* Sprungmarke zum Inhalt (nur bei Tastaturfokus sichtbar) */
+.skip-link {
+    position: absolute;
+    left: 12px;
+    top: -60px;
+    z-index: 999;
+    padding: 10px 16px;
+    background: var(--bg-card);
+    border: 1px solid var(--accent);
+    border-radius: var(--r-md);
+    box-shadow: var(--shadow-md);
+    color: var(--accent);
+    font-size: 13.5px;
+    font-weight: 600;
+    transition: top .15s;
+}
+.skip-link:focus { top: 12px; }
+
+/* Tabellen, die auf schmalen Geräten zu Karten werden.
+   Die Spaltenüberschrift steht dann als data-label vor dem Wert. */
+@media (max-width: 720px) {
+    .table-stack thead { display: none; }
+    .table-stack, .table-stack tbody, .table-stack tr, .table-stack td { display: block; width: 100%; }
+    .table-stack tr {
+        margin-bottom: 10px;
+        padding: 6px 14px;
+        border: 1px solid var(--border-color);
+        border-radius: var(--r-md);
+        background: var(--bg-card);
+    }
+    .table-stack td {
+        display: flex; align-items: center; justify-content: space-between; gap: 14px;
+        padding: 8px 0;
+        border-bottom: 1px solid var(--border-color);
+        text-align: right;
+    }
+    .table-stack tr td:last-child { border-bottom: none; }
+    .table-stack td::before {
+        content: attr(data-label);
+        flex-shrink: 0;
+        color: var(--text-muted);
+        font-size: 11.5px;
+        font-weight: 620;
+        text-transform: uppercase;
+        letter-spacing: .04em;
+        text-align: left;
+    }
+    .table-stack td:not([data-label])::before { content: ''; }
+    .table-stack .details-cell, .table-stack .voucher-note { max-width: none; white-space: normal; }
+}
+
+/* Nutzer, die Bewegung reduzieren möchten, bekommen keine Animationen. */
+@media (prefers-reduced-motion: reduce) {
+    *, *::before, *::after {
+        animation-duration: .001ms !important;
+        animation-iteration-count: 1 !important;
+        transition-duration: .001ms !important;
+        scroll-behavior: auto !important;
+    }
+}
+
 /* =========================================================================
    13. RESPONSIVE
    ========================================================================= */
diff --git a/forgot_password.php b/forgot_password.php
index 9a19fec..de98f60 100644
--- a/forgot_password.php
+++ b/forgot_password.php
@@ -114,7 +114,7 @@ if ($_SERVER['REQUEST_METHOD'] === 'POST') {
     </form>
     <?php endif; ?>
 
-    <div class="auth-links"><a href="login.php" class="back-link"><i class="fas fa-arrow-left"></i> <?= __('reset_back_login') ?></a></div>
+    <div class="auth-links"><a href="login.php" class="back-link"><i class="fas fa-arrow-left" aria-hidden="true"></i> <?= __('reset_back_login') ?></a></div>
 </div>
 <script src="assets/global.js"></script>
 </body>
diff --git a/includes/admin_nav.php b/includes/admin_nav.php
index 189e438..4b5b099 100644
--- a/includes/admin_nav.php
+++ b/includes/admin_nav.php
@@ -48,11 +48,12 @@ foreach ($navGroups as $items) {
 </head>
 <body>
 
+<a class="skip-link" href="#main-content"><?= __('a11y_skip') ?></a>
 <div class="sidebar-overlay" onclick="closeMobileSidebar()"></div>
 
-<aside class="sidebar" id="adminSidebar">
+<aside class="sidebar" id="adminSidebar" aria-label="<?= __('nav_administration') ?>">
     <a href="<?= $rootBase ?>index.php" class="sidebar-brand">
-        <span class="brand-mark"><i class="fas fa-wifi"></i></span>
+        <span class="brand-mark"><i class="fas fa-wifi" aria-hidden="true"></i></span>
         <span class="brand-text">
             <span class="brand-name"><?= htmlspecialchars($appTitle ?? 'Voucher Tool') ?></span>
             <span class="brand-sub"><?= __('nav_administration') ?></span>
@@ -65,8 +66,9 @@ foreach ($navGroups as $items) {
         <ul class="sidebar-nav">
             <?php foreach ($items as [$key, $href, $icon, $labelKey]): ?>
             <li>
-                <a href="<?= $base . $href ?>" class="<?= $currentPage === $key ? 'active' : '' ?>">
-                    <i class="fas <?= $icon ?>"></i> <?= __($labelKey) ?>
+                <a href="<?= $base . $href ?>" class="<?= $currentPage === $key ? 'active' : '' ?>"
+                   <?= $currentPage === $key ? 'aria-current="page"' : '' ?>>
+                    <i class="fas <?= $icon ?>" aria-hidden="true"></i> <?= __($labelKey) ?>
                 </a>
             </li>
             <?php endforeach; ?>
@@ -82,8 +84,8 @@ foreach ($navGroups as $items) {
                 <div class="user-name" style="overflow:hidden;text-overflow:ellipsis;white-space:nowrap;"><?= htmlspecialchars($currentUser['name']) ?></div>
                 <div class="user-role"><?= htmlspecialchars($currentUser['role'] ?? '') ?></div>
             </div>
-            <a href="<?= $rootBase ?>logout.php" class="icon-btn" title="<?= __('btn_logout') ?>" style="width:30px;height:30px;font-size:12px;">
-                <i class="fas fa-arrow-right-from-bracket"></i>
+            <a href="<?= $rootBase ?>logout.php" class="icon-btn" title="<?= __('btn_logout') ?>" aria-label="<?= __('btn_logout') ?>" style="width:30px;height:30px;font-size:12px;">
+                <i class="fas fa-arrow-right-from-bracket" aria-hidden="true"></i>
             </a>
         </div>
     </div>
@@ -92,8 +94,8 @@ foreach ($navGroups as $items) {
 
 <header class="topbar">
     <div class="header-left">
-        <button class="mobile-menu-btn" onclick="toggleMobileSidebar()" title="Menu">
-            <i class="fas fa-bars"></i>
+        <button class="mobile-menu-btn" onclick="toggleMobileSidebar()" aria-label="<?= __('a11y_menu') ?>" title="<?= __('a11y_menu') ?>">
+            <i class="fas fa-bars" aria-hidden="true"></i>
         </button>
         <div class="breadcrumb">
             <span><?= __('nav_administration') ?></span>
@@ -102,20 +104,20 @@ foreach ($navGroups as $items) {
         </div>
     </div>
     <div class="header-right">
-        <div class="lang-switcher">
+        <div class="lang-switcher" role="group" aria-label="<?= __('a11y_language') ?>">
             <?php foreach (I18n::getAvailable() as $code => $label): ?>
             <button class="lang-btn <?= $lang === $code ? 'active' : '' ?>"
                     onclick="switchLanguage('<?= $code ?>')"><?= strtoupper($code) ?></button>
             <?php endforeach; ?>
         </div>
-        <button id="darkModeBtn" class="dark-mode-toggle" onclick="toggleDarkMode()" title="Dark Mode">
-            <i class="fas fa-moon"></i>
+        <button id="darkModeBtn" class="dark-mode-toggle" onclick="toggleDarkMode()" aria-label="<?= __('a11y_theme') ?>" title="<?= __('a11y_theme') ?>">
+            <i class="fas fa-moon" aria-hidden="true"></i>
         </button>
         <a href="<?= $rootBase ?>index.php" class="btn btn-secondary">
-            <i class="fas fa-arrow-left"></i>
+            <i class="fas fa-arrow-left" aria-hidden="true"></i>
             <span class="hide-mobile"><?= __('nav_back') ?></span>
         </a>
     </div>
 </header>
 
-<main class="main-content">
+<main class="main-content" id="main-content">
diff --git a/index.php b/index.php
index 922f458..1919c76 100644
--- a/index.php
+++ b/index.php
@@ -308,43 +308,44 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
 </head>
 <body class="app-body">
 
+<a class="skip-link no-print" href="#main-content"><?= __('a11y_skip') ?></a>
 <header class="app-topbar no-print">
     <a href="index.php" class="brand">
-        <span class="brand-mark"><i class="fas fa-wifi"></i></span>
+        <span class="brand-mark"><i class="fas fa-wifi" aria-hidden="true"></i></span>
         <span class="brand-name"><?= htmlspecialchars($appTitle) ?></span>
     </a>
     <div class="app-actions">
-        <div class="lang-switcher">
+        <div class="lang-switcher" role="group" aria-label="<?= __('a11y_language') ?>">
             <?php foreach (I18n::getAvailable() as $code => $label): ?>
             <button class="lang-btn <?= I18n::getLanguage() === $code ? 'active' : '' ?>"
                     onclick="switchLanguage('<?= $code ?>')"><?= strtoupper($code) ?></button>
             <?php endforeach; ?>
         </div>
-        <button id="darkModeBtn" class="dark-mode-toggle" onclick="toggleDarkMode()" title="Dark Mode">
-            <i class="fas fa-moon"></i>
+        <button id="darkModeBtn" class="dark-mode-toggle" onclick="toggleDarkMode()" aria-label="<?= __('a11y_theme') ?>" title="<?= __('a11y_theme') ?>">
+            <i class="fas fa-moon" aria-hidden="true"></i>
         </button>
         <?php if ($currentUser): ?>
             <?php if ($auth->isAdmin()): ?>
             <a href="admin/" class="btn btn-secondary">
-                <i class="fas fa-sliders"></i> <span class="hide-mobile"><?= __('nav_administration') ?></span>
+                <i class="fas fa-sliders" aria-hidden="true"></i> <span class="hide-mobile"><?= __('nav_administration') ?></span>
             </a>
             <?php endif; ?>
             <div class="user-menu">
                 <div class="user-avatar"><?= strtoupper(mb_substr($currentUser['name'], 0, 1)) ?></div>
                 <div class="user-name hide-mobile"><?= htmlspecialchars($currentUser['name']) ?></div>
-                <a href="logout.php" class="icon-btn" title="<?= __('btn_logout') ?>" style="width:28px;height:28px;font-size:11px;">
-                    <i class="fas fa-arrow-right-from-bracket"></i>
+                <a href="logout.php" class="icon-btn" title="<?= __('btn_logout') ?>" aria-label="<?= __('btn_logout') ?>" style="width:28px;height:28px;font-size:11px;">
+                    <i class="fas fa-arrow-right-from-bracket" aria-hidden="true"></i>
                 </a>
             </div>
         <?php elseif ($publicAccess): ?>
             <a href="login.php" class="btn btn-secondary">
-                <i class="fas fa-right-to-bracket"></i> <?= __('btn_login') ?>
+                <i class="fas fa-right-to-bracket" aria-hidden="true"></i> <?= __('btn_login') ?>
             </a>
         <?php endif; ?>
     </div>
 </header>
 
-<div class="container">
+<main class="container" id="main-content">
     <?php if ($logoUrl && !$voucherCreated && !$bulkCreated): ?>
         <img src="<?= htmlspecialchars(Ui::mediaUrl($logoUrl)) ?>" alt="Logo" class="logo">
     <?php endif; ?>
@@ -366,17 +367,17 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
         </div>
 
         <div class="voucher-result no-print">
-            <div class="result-label"><i class="fas fa-circle-check"></i> <?= __('voucher_success_title') ?></div>
+            <div class="result-label"><i class="fas fa-circle-check" aria-hidden="true"></i> <?= __('voucher_success_title') ?></div>
             <div class="voucher-code" id="voucherCode" onclick="copyCode()" title="<?= __('js_click_to_copy') ?>">
                 <?= htmlspecialchars($voucherCode) ?>
             </div>
             <div class="voucher-info">
-                <i class="fas fa-copy"></i> <?= __('voucher_copy_hint') ?>
+                <i class="fas fa-copy" aria-hidden="true"></i> <?= __('voucher_copy_hint') ?>
             </div>
             <div class="voucher-meta">
-                <span><i class="fas fa-clock"></i> <?= str_replace('{minutes}', $voucherData['expire_min'], __('voucher_validity')) ?></span>
-                <span><i class="fas fa-location-dot"></i> <?= htmlspecialchars($voucherData['site_name']) ?></span>
-                <span><i class="fas fa-mobile-screen"></i> <?= (int)$voucherData['max_uses'] ?> <?= __('label_devices') ?></span>
+                <span><i class="fas fa-clock" aria-hidden="true"></i> <?= str_replace('{minutes}', $voucherData['expire_min'], __('voucher_validity')) ?></span>
+                <span><i class="fas fa-location-dot" aria-hidden="true"></i> <?= htmlspecialchars($voucherData['site_name']) ?></span>
+                <span><i class="fas fa-mobile-screen" aria-hidden="true"></i> <?= (int)$voucherData['max_uses'] ?> <?= __('label_devices') ?></span>
             </div>
             <div class="ticket-divider"></div>
             <div class="qr-wrapper no-print">
@@ -395,11 +396,11 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
         <div class="no-print" style="display:flex;gap:10px;margin-top:18px;">
             <form method="get" style="flex:1;">
                 <button type="submit" class="btn btn-primary btn-lg btn-block">
-                    <i class="fas fa-plus"></i> <?= __('btn_new_code') ?>
+                    <i class="fas fa-plus" aria-hidden="true"></i> <?= __('btn_new_code') ?>
                 </button>
             </form>
             <button onclick="window.print()" class="btn btn-secondary btn-lg">
-                <i class="fas fa-print"></i> <?= __('voucher_print_btn') ?>
+                <i class="fas fa-print" aria-hidden="true"></i> <?= __('voucher_print_btn') ?>
             </button>
         </div>
 
@@ -441,12 +442,12 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
                     <?php endforeach; ?>
                 </tbody>
             </table>
-            <p class="copy-hint"><i class="fas fa-copy"></i> <?= __('voucher_copy_hint') ?></p>
+            <p class="copy-hint"><i class="fas fa-copy" aria-hidden="true"></i> <?= __('voucher_copy_hint') ?></p>
         </div>
 
         <div class="no-print" style="display:flex;gap:10px;margin-top:20px;">
             <button onclick="window.print()" class="btn btn-primary btn-lg" style="flex:1;">
-                <i class="fas fa-print"></i> <?= __('bulk_print_all') ?>
+                <i class="fas fa-print" aria-hidden="true"></i> <?= __('bulk_print_all') ?>
             </button>
             <form method="get" style="flex:1;">
                 <button type="submit" class="btn btn-secondary btn-lg btn-block"><?= __('btn_new_code') ?></button>
@@ -455,7 +456,7 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
 
     <?php elseif (empty($sites)): ?>
         <div class="empty-state">
-            <div class="empty-icon"><i class="fas fa-wifi"></i></div>
+            <div class="empty-icon"><i class="fas fa-wifi" aria-hidden="true"></i></div>
             <p><?= __('voucher_no_sites') ?><br>
             <?php if ($auth->isAdmin()): ?>
                 <a href="admin/" style="color:var(--accent);"><?= __('voucher_no_sites_admin') ?></a>
@@ -539,7 +540,7 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
                     <div class="email-checkbox-wrapper">
                         <input type="checkbox" id="send_email" name="send_email" onchange="toggleEmailField()">
                         <label for="send_email">
-                            <i class="fas fa-envelope" style="color:var(--accent);"></i> <?= __('voucher_email_send') ?>
+                            <i class="fas fa-envelope" style="color:var(--accent);" aria-hidden="true"></i> <?= __('voucher_email_send') ?>
                         </label>
                     </div>
                     <div class="email-input-wrapper" id="email_field">
@@ -556,7 +557,7 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
                 <div class="email-option">
                     <div class="email-checkbox-wrapper">
                         <input type="checkbox" id="send_sms" name="send_sms" onchange="document.getElementById('sms_field').style.display=this.checked?'block':'none'">
-                        <label for="send_sms"><i class="fas fa-comment-sms" style="color:var(--accent);"></i> Code per SMS versenden</label>
+                        <label for="send_sms"><i class="fas fa-comment-sms" style="color:var(--accent);" aria-hidden="true"></i> Code per SMS versenden</label>
                     </div>
                     <div id="sms_field" style="display:none;margin-top:12px;">
                         <label for="recipient_phone">Telefonnummer (international, z.B. +49170…)</label>
@@ -566,7 +567,7 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
                 <?php endif; ?>
 
                 <button type="submit" class="btn btn-primary btn-lg btn-block" id="submitBtn">
-                    <i class="fas fa-ticket"></i> <?= __('voucher_create_btn') ?>
+                    <i class="fas fa-ticket" aria-hidden="true"></i> <?= __('voucher_create_btn') ?>
                 </button>
             </form>
         </div>
@@ -629,9 +630,9 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
         <?php endif; ?>
 
     <?php endif; ?>
-</div>
+</main>
 
-<div id="toast-container"></div>
+<div id="toast-container" role="status" aria-live="polite"></div>
 <script src="assets/global.js"></script>
 <script>
     <?php if ($voucherCreated): ?>
@@ -711,7 +712,7 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
         const btn = document.getElementById('submitBtn');
         if (!btn || btn.disabled) { e.preventDefault(); return; }
         btn.disabled = true;
-        btn.innerHTML = '<i class="fas fa-circle-notch fa-spin"></i> <?= __('voucher_creating') ?>';
+        btn.innerHTML = '<i class="fas fa-circle-notch fa-spin" aria-hidden="true"></i> <?= __('voucher_creating') ?>';
     });
 
     document.getElementById('bulkForm')?.addEventListener('submit', function(e) {
@@ -719,7 +720,7 @@ function buildPrintCard($template, $data, $instructionHeader, $instructionText,
         if (!btn || btn.disabled) { e.preventDefault(); return; }
         const count = document.getElementById('bulk_count').value;
         btn.disabled = true;
-        btn.innerHTML = '<i class="fas fa-circle-notch fa-spin"></i> <?= addslashes(str_replace('{count}', "' + count + '", __('bulk_creating'))) ?>';
+        btn.innerHTML = '<i class="fas fa-circle-notch fa-spin" aria-hidden="true"></i> <?= addslashes(str_replace('{count}', "' + count + '", __('bulk_creating'))) ?>';
     });
 
     document.addEventListener('DOMContentLoaded', function() {
diff --git a/install.php b/install.php
index c6e2f36..0c751ba 100644
--- a/install.php
+++ b/install.php
@@ -1,380 +1,380 @@
-<?php
-session_start();
-
-// Prüfen ob bereits installiert.
-// Wenn eine config.php existiert, darf der Installer NICHT mehr ohne Weiteres
-// erreichbar sein – sonst koennte jeder die Konfiguration ueberschreiben und
-// einen neuen Admin anlegen. Reinstall ist nur fuer angemeldete Admins erlaubt.
-if (file_exists(__DIR__ . '/config.php')) {
-    if (!isset($_GET['reinstall'])) {
-        die('System bereits installiert. Eine Neuinstallation ist nur fuer angemeldete Administratoren ueber install.php?reinstall=1 moeglich.');
-    }
-
-    // Reinstall angefordert -> Admin-Authentifizierung erzwingen
-    require_once __DIR__ . '/config.php';
-    require_once __DIR__ . '/includes/Database.php';
-    require_once __DIR__ . '/includes/Auth.php';
-    try {
-        $reinstallAuth = new Auth();
-        if (!$reinstallAuth->isAdmin()) {
-            die('Neuinstallation nicht erlaubt: Bitte zuerst als Administrator <a href="login.php">anmelden</a>.');
-        }
-    } catch (Exception $e) {
-        die('Neuinstallation nicht moeglich (Konfigurationsfehler).');
-    }
-}
-
-$step = isset($_POST['step']) ? (int)$_POST['step'] : 1;
-$errors = [];
-$success = false;
-
-// Step 1: Datenbankverbindung testen
-if ($step === 2 && $_SERVER['REQUEST_METHOD'] === 'POST') {
-    $db_host = $_POST['db_host'] ?? '';
-    $db_name = $_POST['db_name'] ?? '';
-    $db_user = $_POST['db_user'] ?? '';
-    $db_pass = $_POST['db_pass'] ?? '';
-    
-    try {
-        $pdo = new PDO("mysql:host=$db_host;charset=utf8mb4", $db_user, $db_pass);
-        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
-        
-        // Datenbank erstellen falls nicht vorhanden
-        $pdo->exec("CREATE DATABASE IF NOT EXISTS `$db_name` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
-        $pdo->exec("USE `$db_name`");
-        
-        // Tabellen erstellen
-        $sql = file_get_contents(__DIR__ . '/database.sql');
-        $pdo->exec($sql);
-        
-        $_SESSION['install_db'] = [
-            'host' => $db_host,
-            'name' => $db_name,
-            'user' => $db_user,
-            'pass' => $db_pass
-        ];
-        
-    } catch (PDOException $e) {
-        $errors[] = "Datenbankfehler: " . $e->getMessage();
-        $step = 1;
-    }
-}
-
-// Step 2: Admin-Account erstellen
-if ($step === 3 && $_SERVER['REQUEST_METHOD'] === 'POST') {
-    $admin_email = filter_var($_POST['admin_email'] ?? '', FILTER_VALIDATE_EMAIL);
-    $admin_name = $_POST['admin_name'] ?? '';
-    $admin_password = $_POST['admin_password'] ?? '';
-    $admin_password_confirm = $_POST['admin_password_confirm'] ?? '';
-    
-    if (!$admin_email) {
-        $errors[] = "Ungültige E-Mail-Adresse";
-        $step = 2;
-    } elseif (strlen($admin_password) < 8) {
-        $errors[] = "Passwort muss mindestens 8 Zeichen lang sein";
-        $step = 2;
-    } elseif ($admin_password !== $admin_password_confirm) {
-        $errors[] = "Passwörter stimmen nicht überein";
-        $step = 2;
-    } else {
-        $_SESSION['install_admin'] = [
-            'email' => $admin_email,
-            'name' => $admin_name,
-            'password' => password_hash($admin_password, PASSWORD_DEFAULT)
-        ];
-    }
-}
-
-// Step 3: Allgemeine Einstellungen
-if ($step === 4 && $_SERVER['REQUEST_METHOD'] === 'POST') {
-    $app_title = $_POST['app_title'] ?? 'UniFi Voucher System';
-    $logo_url = $_POST['logo_url'] ?? '';
-    $instruction_header = $_POST['instruction_header'] ?? '';
-    $instruction_text = $_POST['instruction_text'] ?? '';
-    $public_access = isset($_POST['public_access']) ? 1 : 0;
-    
-    // Microsoft 365 OAuth (optional)
-    $m365_client_id = $_POST['m365_client_id'] ?? '';
-    $m365_client_secret = $_POST['m365_client_secret'] ?? '';
-    $m365_tenant_id = $_POST['m365_tenant_id'] ?? '';
-    
-    $_SESSION['install_settings'] = [
-        'app_title' => $app_title,
-        'logo_url' => $logo_url,
-        'instruction_header' => $instruction_header,
-        'instruction_text' => $instruction_text,
-        'public_access' => $public_access,
-        'm365_client_id' => $m365_client_id,
-        'm365_client_secret' => $m365_client_secret,
-        'm365_tenant_id' => $m365_tenant_id
-    ];
-}
-
-// Step 4: Installation abschließen
-if ($step === 5 && $_SERVER['REQUEST_METHOD'] === 'POST') {
-    try {
-        $db = $_SESSION['install_db'];
-        $admin = $_SESSION['install_admin'];
-        $settings = $_SESSION['install_settings'];
-        
-        $pdo = new PDO("mysql:host={$db['host']};dbname={$db['name']};charset=utf8mb4", $db['user'], $db['pass']);
-        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
-        
-        // Admin-User erstellen
-        $stmt = $pdo->prepare("INSERT INTO users (email, name, password_hash, is_admin, is_active) VALUES (?, ?, ?, 1, 1)");
-        $stmt->execute([$admin['email'], $admin['name'], $admin['password']]);
-        
-        // Settings speichern
-        $settingsData = [
-            'app_title' => $settings['app_title'],
-            'logo_url' => $settings['logo_url'],
-            'instruction_header' => $settings['instruction_header'],
-            'instruction_text' => $settings['instruction_text'],
-            'public_access' => $settings['public_access'],
-            'm365_client_id' => $settings['m365_client_id'],
-            'm365_client_secret' => $settings['m365_client_secret'],
-            'm365_tenant_id' => $settings['m365_tenant_id']
-        ];
-        
-        $stmt = $pdo->prepare("INSERT INTO settings (setting_key, setting_value) VALUES (?, ?) ON DUPLICATE KEY UPDATE setting_value = VALUES(setting_value)");
-        foreach ($settingsData as $key => $value) {
-            $stmt->execute([$key, $value]);
-        }
-        
-        // config.php erstellen
-        $configContent = "<?php\n";
-        $configContent .= "// UniFi Voucher Management System - Configuration\n\n";
-        $configContent .= "define('DB_HOST', '{$db['host']}');\n";
-        $configContent .= "define('DB_NAME', '{$db['name']}');\n";
-        $configContent .= "define('DB_USER', '{$db['user']}');\n";
-        $configContent .= "define('DB_PASS', '" . addslashes($db['pass']) . "');\n\n";
-        $configContent .= "// Anwendungs-Schluessel fuer Verschluesselung-at-rest (z.B. UniFi-Passwoerter)\n";
-        $configContent .= "// NICHT aendern, sonst koennen bestehende verschluesselte Werte nicht mehr gelesen werden.\n";
-        $configContent .= "define('APP_KEY', '" . base64_encode(random_bytes(32)) . "');\n\n";
-        $configContent .= "// Sitzungs-Einstellungen\n";
-        $configContent .= "define('SESSION_LIFETIME', 3600); // 1 Stunde\n\n";
-        $configContent .= "// Zeitzone\n";
-        $configContent .= "date_default_timezone_set('Europe/Berlin');\n";
-        
-        file_put_contents(__DIR__ . '/config.php', $configContent);
-        
-        // .htaccess erstellen (ohne Rewrite Rules die Probleme machen)
-        $htaccess = "# UniFi Voucher System\n\n";
-        $htaccess .= "# Security\n";
-        $htaccess .= "<FilesMatch \"(config\\.php|database\\.sql|install\\.php|test\\.php|m365_debug\\.php|\\.md)$\">\n";
-        $htaccess .= "    Order Allow,Deny\n";
-        $htaccess .= "    Deny from all\n";
-        $htaccess .= "</FilesMatch>\n\n";
-        $htaccess .= "DirectoryIndex index.php\n";
-        file_put_contents(__DIR__ . '/.htaccess', $htaccess);
-        
-        $success = true;
-        
-        // Session-Daten löschen
-        unset($_SESSION['install_db'], $_SESSION['install_admin'], $_SESSION['install_settings']);
-        
-    } catch (Exception $e) {
-        $errors[] = "Fehler bei der Installation: " . $e->getMessage();
-        $step = 4;
-    }
-}
-?>
-<!DOCTYPE html>
-<html lang="de">
-<head>
-    <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>UniFi Voucher System - Installation</title>
-    <?php require_once __DIR__ . '/includes/Ui.php'; ?>
-    <?= Ui::head(null) ?>
-    <style>
-        /* Installer-spezifisch: Fortschrittsanzeige und Abschnitte */
-        .install-head { display: flex; align-items: center; gap: 14px; margin-bottom: 4px; }
-        .progress { position: relative; display: flex; justify-content: space-between; margin: 26px 0 28px; }
-        .progress::before {
-            content: ''; position: absolute; top: 14px; left: 14px; right: 14px;
-            height: 2px; background: var(--border-color); z-index: 0;
-        }
-        .progress-step {
-            position: relative; z-index: 1;
-            width: 28px; height: 28px; border-radius: 50%;
-            display: flex; align-items: center; justify-content: center;
-            background: var(--bg-card); border: 1px solid var(--border-color);
-            color: var(--text-muted); font-size: 12px; font-weight: 650;
-        }
-        .progress-step.active    { background: var(--accent); border-color: var(--accent); color: #fff; box-shadow: var(--ring); }
-        .progress-step.completed { background: var(--success); border-color: var(--success); color: #fff; }
-        .section {
-            padding: 18px;
-            margin-bottom: 20px;
-            background: var(--bg-subtle);
-            border: 1px solid var(--border-color);
-            border-radius: var(--r-md);
-        }
-        .section h3 { font-size: 14px; margin-bottom: 14px; }
-        .error, .success {
-            padding: 12px 15px; margin-bottom: 20px;
-            border-radius: var(--r-md); font-size: 13.5px;
-            border: 1px solid var(--danger-border); background: var(--danger-soft); color: var(--danger);
-        }
-        .success { border-color: var(--success-border); background: var(--success-soft); color: var(--success); }
-        form > h3 { font-size: 15px; margin-bottom: 16px; }
-    </style>
-</head>
-<body class="app-body focus-page">
-    <div class="focus-card card">
-        <div class="install-head">
-            <span class="focus-icon"><i class="fas fa-rocket"></i></span>
-            <div>
-                <h1 style="font-size:20px;">UniFi Voucher System</h1>
-                <p class="sub">Installation in fünf Schritten</p>
-            </div>
-        </div>
-        
-        <div class="progress">
-            <div class="progress-step <?= $step >= 1 ? 'completed' : '' ?>">1</div>
-            <div class="progress-step <?= $step >= 2 ? 'completed' : ($step === 1 ? 'active' : '') ?>">2</div>
-            <div class="progress-step <?= $step >= 3 ? 'completed' : ($step === 2 ? 'active' : '') ?>">3</div>
-            <div class="progress-step <?= $step >= 4 ? 'completed' : ($step === 3 ? 'active' : '') ?>">4</div>
-            <div class="progress-step <?= $step >= 5 ? 'active' : '' ?>">5</div>
-        </div>
-        
-        <?php if (!empty($errors)): ?>
-            <div class="error">
-                <?php foreach ($errors as $error): ?>
-                    <div><?= htmlspecialchars($error) ?></div>
-                <?php endforeach; ?>
-            </div>
-        <?php endif; ?>
-        
-        <?php if ($success): ?>
-            <div class="success">
-                <strong>✓ Installation erfolgreich abgeschlossen!</strong><br>
-                Sie können sich jetzt mit Ihren Admin-Zugangsdaten anmelden.
-            </div>
-            <a href="index.php" class="btn btn-primary btn-lg btn-block">Zum Login</a>
-        <?php elseif ($step === 1): ?>
-            <form method="post">
-                <input type="hidden" name="step" value="2">
-                <h3>Schritt 1: Datenbank-Konfiguration</h3>
-                
-                <div class="form-group">
-                    <label>Datenbank-Host</label>
-                    <input type="text" name="db_host" value="localhost" required>
-                    <div class="help-text">Meist "localhost"</div>
-                </div>
-                
-                <div class="form-group">
-                    <label>Datenbankname</label>
-                    <input type="text" name="db_name" value="unifi_voucher" required>
-                    <div class="help-text">Name der Datenbank (wird erstellt falls nicht vorhanden)</div>
-                </div>
-                
-                <div class="form-group">
-                    <label>Datenbank-Benutzer</label>
-                    <input type="text" name="db_user" required>
-                </div>
-                
-                <div class="form-group">
-                    <label>Datenbank-Passwort</label>
-                    <input type="password" name="db_pass">
-                </div>
-                
-                <button type="submit" class="btn btn-primary btn-lg btn-block">Weiter <i class="fas fa-arrow-right"></i></button>
-            </form>
-        
-        <?php elseif ($step === 2): ?>
-            <form method="post">
-                <input type="hidden" name="step" value="3">
-                <h3>Schritt 2: Administrator-Account</h3>
-                
-                <div class="form-group">
-                    <label>Name</label>
-                    <input type="text" name="admin_name" required>
-                </div>
-                
-                <div class="form-group">
-                    <label>E-Mail</label>
-                    <input type="email" name="admin_email" required>
-                </div>
-                
-                <div class="form-group">
-                    <label>Passwort</label>
-                    <input type="password" name="admin_password" required minlength="8">
-                    <div class="help-text">Mindestens 8 Zeichen</div>
-                </div>
-                
-                <div class="form-group">
-                    <label>Passwort bestätigen</label>
-                    <input type="password" name="admin_password_confirm" required>
-                </div>
-                
-                <button type="submit" class="btn btn-primary btn-lg btn-block">Weiter <i class="fas fa-arrow-right"></i></button>
-            </form>
-        
-        <?php elseif ($step === 3): ?>
-            <form method="post">
-                <input type="hidden" name="step" value="4">
-                <h3>Schritt 3: Allgemeine Einstellungen</h3>
-                
-                <div class="form-group">
-                    <label>Anwendungs-Titel</label>
-                    <input type="text" name="app_title" value="UniFi Voucher System" required>
-                </div>
-                
-                <div class="form-group">
-                    <label>Logo-URL (optional)</label>
-                    <input type="text" name="logo_url" placeholder="https://example.com/logo.png">
-                </div>
-                
-                <div class="form-group">
-                    <label>Anleitung Überschrift</label>
-                    <input type="text" name="instruction_header" value="So verwenden Sie Ihren Code">
-                </div>
-                
-                <div class="form-group">
-                    <label>Anleitung Text</label>
-                    <textarea name="instruction_text">Verbinden Sie sich mit dem WLAN und geben Sie den Code auf der Anmeldeseite ein.</textarea>
-                </div>
-                
-                <div class="form-group checkbox-group">
-                    <input type="checkbox" name="public_access" id="public_access">
-                    <label for="public_access" style="margin: 0;">Öffentlicher Zugriff auf Code-Erstellung</label>
-                </div>
-                
-                <div class="section">
-                    <h3>Microsoft 365 Login (Optional)</h3>
-                    <div class="form-group">
-                        <label>Client ID</label>
-                        <input type="text" name="m365_client_id">
-                    </div>
-                    <div class="form-group">
-                        <label>Client Secret</label>
-                        <input type="password" name="m365_client_secret">
-                    </div>
-                    <div class="form-group">
-                        <label>Tenant ID</label>
-                        <input type="text" name="m365_tenant_id">
-                    </div>
-                    <div class="help-text">Leer lassen, wenn M365-Login nicht verwendet werden soll</div>
-                </div>
-                
-                <button type="submit" class="btn btn-primary btn-lg btn-block">Weiter <i class="fas fa-arrow-right"></i></button>
-            </form>
-        
-        <?php elseif ($step === 4): ?>
-            <form method="post">
-                <input type="hidden" name="step" value="5">
-                <h3>Schritt 4: Installation abschließen</h3>
-                
-                <p style="margin-bottom: 20px; color: #666;">
-                    Klicken Sie auf "Installation abschließen", um die Einrichtung zu beenden.
-                    Die Datenbank und alle notwendigen Dateien werden erstellt.
-                </p>
-                
-                <button type="submit" class="btn btn-primary btn-lg btn-block">Installation abschließen</button>
-            </form>
-        <?php endif; ?>
-    </div>
-</body>
+<?php
+session_start();
+
+// Prüfen ob bereits installiert.
+// Wenn eine config.php existiert, darf der Installer NICHT mehr ohne Weiteres
+// erreichbar sein – sonst koennte jeder die Konfiguration ueberschreiben und
+// einen neuen Admin anlegen. Reinstall ist nur fuer angemeldete Admins erlaubt.
+if (file_exists(__DIR__ . '/config.php')) {
+    if (!isset($_GET['reinstall'])) {
+        die('System bereits installiert. Eine Neuinstallation ist nur fuer angemeldete Administratoren ueber install.php?reinstall=1 moeglich.');
+    }
+
+    // Reinstall angefordert -> Admin-Authentifizierung erzwingen
+    require_once __DIR__ . '/config.php';
+    require_once __DIR__ . '/includes/Database.php';
+    require_once __DIR__ . '/includes/Auth.php';
+    try {
+        $reinstallAuth = new Auth();
+        if (!$reinstallAuth->isAdmin()) {
+            die('Neuinstallation nicht erlaubt: Bitte zuerst als Administrator <a href="login.php">anmelden</a>.');
+        }
+    } catch (Exception $e) {
+        die('Neuinstallation nicht moeglich (Konfigurationsfehler).');
+    }
+}
+
+$step = isset($_POST['step']) ? (int)$_POST['step'] : 1;
+$errors = [];
+$success = false;
+
+// Step 1: Datenbankverbindung testen
+if ($step === 2 && $_SERVER['REQUEST_METHOD'] === 'POST') {
+    $db_host = $_POST['db_host'] ?? '';
+    $db_name = $_POST['db_name'] ?? '';
+    $db_user = $_POST['db_user'] ?? '';
+    $db_pass = $_POST['db_pass'] ?? '';
+    
+    try {
+        $pdo = new PDO("mysql:host=$db_host;charset=utf8mb4", $db_user, $db_pass);
+        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+        
+        // Datenbank erstellen falls nicht vorhanden
+        $pdo->exec("CREATE DATABASE IF NOT EXISTS `$db_name` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
+        $pdo->exec("USE `$db_name`");
+        
+        // Tabellen erstellen
+        $sql = file_get_contents(__DIR__ . '/database.sql');
+        $pdo->exec($sql);
+        
+        $_SESSION['install_db'] = [
+            'host' => $db_host,
+            'name' => $db_name,
+            'user' => $db_user,
+            'pass' => $db_pass
+        ];
+        
+    } catch (PDOException $e) {
+        $errors[] = "Datenbankfehler: " . $e->getMessage();
+        $step = 1;
+    }
+}
+
+// Step 2: Admin-Account erstellen
+if ($step === 3 && $_SERVER['REQUEST_METHOD'] === 'POST') {
+    $admin_email = filter_var($_POST['admin_email'] ?? '', FILTER_VALIDATE_EMAIL);
+    $admin_name = $_POST['admin_name'] ?? '';
+    $admin_password = $_POST['admin_password'] ?? '';
+    $admin_password_confirm = $_POST['admin_password_confirm'] ?? '';
+    
+    if (!$admin_email) {
+        $errors[] = "Ungültige E-Mail-Adresse";
+        $step = 2;
+    } elseif (strlen($admin_password) < 8) {
+        $errors[] = "Passwort muss mindestens 8 Zeichen lang sein";
+        $step = 2;
+    } elseif ($admin_password !== $admin_password_confirm) {
+        $errors[] = "Passwörter stimmen nicht überein";
+        $step = 2;
+    } else {
+        $_SESSION['install_admin'] = [
+            'email' => $admin_email,
+            'name' => $admin_name,
+            'password' => password_hash($admin_password, PASSWORD_DEFAULT)
+        ];
+    }
+}
+
+// Step 3: Allgemeine Einstellungen
+if ($step === 4 && $_SERVER['REQUEST_METHOD'] === 'POST') {
+    $app_title = $_POST['app_title'] ?? 'UniFi Voucher System';
+    $logo_url = $_POST['logo_url'] ?? '';
+    $instruction_header = $_POST['instruction_header'] ?? '';
+    $instruction_text = $_POST['instruction_text'] ?? '';
+    $public_access = isset($_POST['public_access']) ? 1 : 0;
+    
+    // Microsoft 365 OAuth (optional)
+    $m365_client_id = $_POST['m365_client_id'] ?? '';
+    $m365_client_secret = $_POST['m365_client_secret'] ?? '';
+    $m365_tenant_id = $_POST['m365_tenant_id'] ?? '';
+    
+    $_SESSION['install_settings'] = [
+        'app_title' => $app_title,
+        'logo_url' => $logo_url,
+        'instruction_header' => $instruction_header,
+        'instruction_text' => $instruction_text,
+        'public_access' => $public_access,
+        'm365_client_id' => $m365_client_id,
+        'm365_client_secret' => $m365_client_secret,
+        'm365_tenant_id' => $m365_tenant_id
+    ];
+}
+
+// Step 4: Installation abschließen
+if ($step === 5 && $_SERVER['REQUEST_METHOD'] === 'POST') {
+    try {
+        $db = $_SESSION['install_db'];
+        $admin = $_SESSION['install_admin'];
+        $settings = $_SESSION['install_settings'];
+        
+        $pdo = new PDO("mysql:host={$db['host']};dbname={$db['name']};charset=utf8mb4", $db['user'], $db['pass']);
+        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+        
+        // Admin-User erstellen
+        $stmt = $pdo->prepare("INSERT INTO users (email, name, password_hash, is_admin, is_active) VALUES (?, ?, ?, 1, 1)");
+        $stmt->execute([$admin['email'], $admin['name'], $admin['password']]);
+        
+        // Settings speichern
+        $settingsData = [
+            'app_title' => $settings['app_title'],
+            'logo_url' => $settings['logo_url'],
+            'instruction_header' => $settings['instruction_header'],
+            'instruction_text' => $settings['instruction_text'],
+            'public_access' => $settings['public_access'],
+            'm365_client_id' => $settings['m365_client_id'],
+            'm365_client_secret' => $settings['m365_client_secret'],
+            'm365_tenant_id' => $settings['m365_tenant_id']
+        ];
+        
+        $stmt = $pdo->prepare("INSERT INTO settings (setting_key, setting_value) VALUES (?, ?) ON DUPLICATE KEY UPDATE setting_value = VALUES(setting_value)");
+        foreach ($settingsData as $key => $value) {
+            $stmt->execute([$key, $value]);
+        }
+        
+        // config.php erstellen
+        $configContent = "<?php\n";
+        $configContent .= "// UniFi Voucher Management System - Configuration\n\n";
+        $configContent .= "define('DB_HOST', '{$db['host']}');\n";
+        $configContent .= "define('DB_NAME', '{$db['name']}');\n";
+        $configContent .= "define('DB_USER', '{$db['user']}');\n";
+        $configContent .= "define('DB_PASS', '" . addslashes($db['pass']) . "');\n\n";
+        $configContent .= "// Anwendungs-Schluessel fuer Verschluesselung-at-rest (z.B. UniFi-Passwoerter)\n";
+        $configContent .= "// NICHT aendern, sonst koennen bestehende verschluesselte Werte nicht mehr gelesen werden.\n";
+        $configContent .= "define('APP_KEY', '" . base64_encode(random_bytes(32)) . "');\n\n";
+        $configContent .= "// Sitzungs-Einstellungen\n";
+        $configContent .= "define('SESSION_LIFETIME', 3600); // 1 Stunde\n\n";
+        $configContent .= "// Zeitzone\n";
+        $configContent .= "date_default_timezone_set('Europe/Berlin');\n";
+        
+        file_put_contents(__DIR__ . '/config.php', $configContent);
+        
+        // .htaccess erstellen (ohne Rewrite Rules die Probleme machen)
+        $htaccess = "# UniFi Voucher System\n\n";
+        $htaccess .= "# Security\n";
+        $htaccess .= "<FilesMatch \"(config\\.php|database\\.sql|install\\.php|test\\.php|m365_debug\\.php|\\.md)$\">\n";
+        $htaccess .= "    Order Allow,Deny\n";
+        $htaccess .= "    Deny from all\n";
+        $htaccess .= "</FilesMatch>\n\n";
+        $htaccess .= "DirectoryIndex index.php\n";
+        file_put_contents(__DIR__ . '/.htaccess', $htaccess);
+        
+        $success = true;
+        
+        // Session-Daten löschen
+        unset($_SESSION['install_db'], $_SESSION['install_admin'], $_SESSION['install_settings']);
+        
+    } catch (Exception $e) {
+        $errors[] = "Fehler bei der Installation: " . $e->getMessage();
+        $step = 4;
+    }
+}
+?>
+<!DOCTYPE html>
+<html lang="de">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>UniFi Voucher System - Installation</title>
+    <?php require_once __DIR__ . '/includes/Ui.php'; ?>
+    <?= Ui::head(null) ?>
+    <style>
+        /* Installer-spezifisch: Fortschrittsanzeige und Abschnitte */
+        .install-head { display: flex; align-items: center; gap: 14px; margin-bottom: 4px; }
+        .progress { position: relative; display: flex; justify-content: space-between; margin: 26px 0 28px; }
+        .progress::before {
+            content: ''; position: absolute; top: 14px; left: 14px; right: 14px;
+            height: 2px; background: var(--border-color); z-index: 0;
+        }
+        .progress-step {
+            position: relative; z-index: 1;
+            width: 28px; height: 28px; border-radius: 50%;
+            display: flex; align-items: center; justify-content: center;
+            background: var(--bg-card); border: 1px solid var(--border-color);
+            color: var(--text-muted); font-size: 12px; font-weight: 650;
+        }
+        .progress-step.active    { background: var(--accent); border-color: var(--accent); color: #fff; box-shadow: var(--ring); }
+        .progress-step.completed { background: var(--success); border-color: var(--success); color: #fff; }
+        .section {
+            padding: 18px;
+            margin-bottom: 20px;
+            background: var(--bg-subtle);
+            border: 1px solid var(--border-color);
+            border-radius: var(--r-md);
+        }
+        .section h3 { font-size: 14px; margin-bottom: 14px; }
+        .error, .success {
+            padding: 12px 15px; margin-bottom: 20px;
+            border-radius: var(--r-md); font-size: 13.5px;
+            border: 1px solid var(--danger-border); background: var(--danger-soft); color: var(--danger);
+        }
+        .success { border-color: var(--success-border); background: var(--success-soft); color: var(--success); }
+        form > h3 { font-size: 15px; margin-bottom: 16px; }
+    </style>
+</head>
+<body class="app-body focus-page">
+    <div class="focus-card card">
+        <div class="install-head">
+            <span class="focus-icon"><i class="fas fa-rocket" aria-hidden="true"></i></span>
+            <div>
+                <h1 style="font-size:20px;">UniFi Voucher System</h1>
+                <p class="sub">Installation in fünf Schritten</p>
+            </div>
+        </div>
+        
+        <div class="progress">
+            <div class="progress-step <?= $step >= 1 ? 'completed' : '' ?>">1</div>
+            <div class="progress-step <?= $step >= 2 ? 'completed' : ($step === 1 ? 'active' : '') ?>">2</div>
+            <div class="progress-step <?= $step >= 3 ? 'completed' : ($step === 2 ? 'active' : '') ?>">3</div>
+            <div class="progress-step <?= $step >= 4 ? 'completed' : ($step === 3 ? 'active' : '') ?>">4</div>
+            <div class="progress-step <?= $step >= 5 ? 'active' : '' ?>">5</div>
+        </div>
+        
+        <?php if (!empty($errors)): ?>
+            <div class="error">
+                <?php foreach ($errors as $error): ?>
+                    <div><?= htmlspecialchars($error) ?></div>
+                <?php endforeach; ?>
+            </div>
+        <?php endif; ?>
+        
+        <?php if ($success): ?>
+            <div class="success">
+                <strong>✓ Installation erfolgreich abgeschlossen!</strong><br>
+                Sie können sich jetzt mit Ihren Admin-Zugangsdaten anmelden.
+            </div>
+            <a href="index.php" class="btn btn-primary btn-lg btn-block">Zum Login</a>
+        <?php elseif ($step === 1): ?>
+            <form method="post">
+                <input type="hidden" name="step" value="2">
+                <h3>Schritt 1: Datenbank-Konfiguration</h3>
+                
+                <div class="form-group">
+                    <label>Datenbank-Host</label>
+                    <input type="text" name="db_host" value="localhost" required>
+                    <div class="help-text">Meist "localhost"</div>
+                </div>
+                
+                <div class="form-group">
+                    <label>Datenbankname</label>
+                    <input type="text" name="db_name" value="unifi_voucher" required>
+                    <div class="help-text">Name der Datenbank (wird erstellt falls nicht vorhanden)</div>
+                </div>
+                
+                <div class="form-group">
+                    <label>Datenbank-Benutzer</label>
+                    <input type="text" name="db_user" required>
+                </div>
+                
+                <div class="form-group">
+                    <label>Datenbank-Passwort</label>
+                    <input type="password" name="db_pass">
+                </div>
+                
+                <button type="submit" class="btn btn-primary btn-lg btn-block">Weiter <i class="fas fa-arrow-right" aria-hidden="true"></i></button>
+            </form>
+        
+        <?php elseif ($step === 2): ?>
+            <form method="post">
+                <input type="hidden" name="step" value="3">
+                <h3>Schritt 2: Administrator-Account</h3>
+                
+                <div class="form-group">
+                    <label>Name</label>
+                    <input type="text" name="admin_name" required>
+                </div>
+                
+                <div class="form-group">
+                    <label>E-Mail</label>
+                    <input type="email" name="admin_email" required>
+                </div>
+                
+                <div class="form-group">
+                    <label>Passwort</label>
+                    <input type="password" name="admin_password" required minlength="8">
+                    <div class="help-text">Mindestens 8 Zeichen</div>
+                </div>
+                
+                <div class="form-group">
+                    <label>Passwort bestätigen</label>
+                    <input type="password" name="admin_password_confirm" required>
+                </div>
+                
+                <button type="submit" class="btn btn-primary btn-lg btn-block">Weiter <i class="fas fa-arrow-right" aria-hidden="true"></i></button>
+            </form>
+        
+        <?php elseif ($step === 3): ?>
+            <form method="post">
+                <input type="hidden" name="step" value="4">
+                <h3>Schritt 3: Allgemeine Einstellungen</h3>
+                
+                <div class="form-group">
+                    <label>Anwendungs-Titel</label>
+                    <input type="text" name="app_title" value="UniFi Voucher System" required>
+                </div>
+                
+                <div class="form-group">
+                    <label>Logo-URL (optional)</label>
+                    <input type="text" name="logo_url" placeholder="https://example.com/logo.png">
+                </div>
+                
+                <div class="form-group">
+                    <label>Anleitung Überschrift</label>
+                    <input type="text" name="instruction_header" value="So verwenden Sie Ihren Code">
+                </div>
+                
+                <div class="form-group">
+                    <label>Anleitung Text</label>
+                    <textarea name="instruction_text">Verbinden Sie sich mit dem WLAN und geben Sie den Code auf der Anmeldeseite ein.</textarea>
+                </div>
+                
+                <div class="form-group checkbox-group">
+                    <input type="checkbox" name="public_access" id="public_access">
+                    <label for="public_access" style="margin: 0;">Öffentlicher Zugriff auf Code-Erstellung</label>
+                </div>
+                
+                <div class="section">
+                    <h3>Microsoft 365 Login (Optional)</h3>
+                    <div class="form-group">
+                        <label>Client ID</label>
+                        <input type="text" name="m365_client_id">
+                    </div>
+                    <div class="form-group">
+                        <label>Client Secret</label>
+                        <input type="password" name="m365_client_secret">
+                    </div>
+                    <div class="form-group">
+                        <label>Tenant ID</label>
+                        <input type="text" name="m365_tenant_id">
+                    </div>
+                    <div class="help-text">Leer lassen, wenn M365-Login nicht verwendet werden soll</div>
+                </div>
+                
+                <button type="submit" class="btn btn-primary btn-lg btn-block">Weiter <i class="fas fa-arrow-right" aria-hidden="true"></i></button>
+            </form>
+        
+        <?php elseif ($step === 4): ?>
+            <form method="post">
+                <input type="hidden" name="step" value="5">
+                <h3>Schritt 4: Installation abschließen</h3>
+                
+                <p style="margin-bottom: 20px; color: #666;">
+                    Klicken Sie auf "Installation abschließen", um die Einrichtung zu beenden.
+                    Die Datenbank und alle notwendigen Dateien werden erstellt.
+                </p>
+                
+                <button type="submit" class="btn btn-primary btn-lg btn-block">Installation abschließen</button>
+            </form>
+        <?php endif; ?>
+    </div>
+</body>
 </html>
\ No newline at end of file
diff --git a/lang/de.php b/lang/de.php
index 10a8504..8680307 100644
--- a/lang/de.php
+++ b/lang/de.php
@@ -455,6 +455,15 @@ return [
     'audit_action_template_updated' => 'Profil geändert',
     'audit_action_template_deleted' => 'Profil gelöscht',
     'audit_page_info'              => 'Seite {page} von {pages} ({total} Einträge)',
+    'a11y_skip'                    => 'Zum Inhalt springen',
+    'a11y_theme'                   => 'Darstellung umschalten (hell/dunkel)',
+    'a11y_menu'                    => 'Navigation öffnen',
+    'a11y_language'                => 'Sprache',
+    'a11y_notifications'           => 'Benachrichtigungen',
+    'audit_system_anon'            => 'System/Anonym',
+    'vouchers_resend'              => 'Per E-Mail senden',
+    'label_minutes_short'          => 'Min.',
+    'js_copy'                      => 'Kopieren',
     'settings_tab_general'  => 'Allgemein',
     'settings_tab_defaults' => 'Voucher-Standards',
     'settings_tab_cron'     => 'Cron-Sync',
diff --git a/lang/en.php b/lang/en.php
index b33e6f3..ec58117 100644
--- a/lang/en.php
+++ b/lang/en.php
@@ -455,6 +455,15 @@ return [
     'audit_action_template_updated' => 'Profile updated',
     'audit_action_template_deleted' => 'Profile deleted',
     'audit_page_info'              => 'Page {page} of {pages} ({total} entries)',
+    'a11y_skip'                    => 'Skip to content',
+    'a11y_theme'                   => 'Toggle appearance (light/dark)',
+    'a11y_menu'                    => 'Open navigation',
+    'a11y_language'                => 'Language',
+    'a11y_notifications'           => 'Notifications',
+    'audit_system_anon'            => 'System/anonymous',
+    'vouchers_resend'              => 'Send by email',
+    'label_minutes_short'          => 'min',
+    'js_copy'                      => 'Copy',
     'settings_tab_general'  => 'General',
     'settings_tab_defaults' => 'Voucher Defaults',
     'settings_tab_cron'     => 'Cron Sync',
diff --git a/login.php b/login.php
index 3531633..195d4d6 100644
--- a/login.php
+++ b/login.php
@@ -169,7 +169,7 @@ try {
         <?php if ($loginLogo): ?>
             <img src="<?= htmlspecialchars(Ui::mediaUrl($loginLogo)) ?>" alt="<?= htmlspecialchars($loginBrand) ?>" class="auth-brand-logo">
         <?php else: ?>
-            <span class="brand-mark"><i class="fas fa-wifi"></i></span>
+            <span class="brand-mark"><i class="fas fa-wifi" aria-hidden="true"></i></span>
             <span><?= htmlspecialchars($loginBrand) ?></span>
         <?php endif; ?>
     </div>
@@ -179,7 +179,7 @@ try {
         <?php if (!empty($loginFeatures)): ?>
         <ul class="auth-features">
             <?php foreach ($loginFeatures as $feature): ?>
-            <li><span class="tick"><i class="fas fa-check"></i></span> <?= htmlspecialchars($feature) ?></li>
+            <li><span class="tick"><i class="fas fa-check" aria-hidden="true"></i></span> <?= htmlspecialchars($feature) ?></li>
             <?php endforeach; ?>
         </ul>
         <?php endif; ?>
@@ -190,14 +190,14 @@ try {
 
 <section class="auth-panel">
     <div class="auth-tools">
-        <div class="lang-switcher">
+        <div class="lang-switcher" role="group" aria-label="<?= __('a11y_language') ?>">
             <?php foreach (I18n::getAvailable() as $code => $label): ?>
             <button class="lang-btn <?= I18n::getLanguage() === $code ? 'active' : '' ?>"
                     onclick="switchLanguage('<?= $code ?>')"><?= strtoupper($code) ?></button>
             <?php endforeach; ?>
         </div>
-        <button id="darkModeBtn" class="dark-mode-toggle" onclick="toggleDarkMode()" title="Dark Mode">
-            <i class="fas fa-moon"></i>
+        <button id="darkModeBtn" class="dark-mode-toggle" onclick="toggleDarkMode()" aria-label="<?= __('a11y_theme') ?>" title="<?= __('a11y_theme') ?>">
+            <i class="fas fa-moon" aria-hidden="true"></i>
         </button>
     </div>
 
@@ -207,7 +207,7 @@ try {
             <img src="<?= htmlspecialchars(Ui::mediaUrl($loginLogo)) ?>" alt="<?= htmlspecialchars($loginBrand) ?>" class="logo">
         <?php else: ?>
             <div class="auth-mark">
-                <span class="brand-mark"><i class="fas fa-wifi"></i></span>
+                <span class="brand-mark"><i class="fas fa-wifi" aria-hidden="true"></i></span>
                 <span><?= htmlspecialchars($loginBrand) ?></span>
             </div>
         <?php endif; ?>
@@ -281,12 +281,12 @@ try {
     <?php if (!$show2fa && $oidcEnabled): ?>
         <div class="divider"><span><?= __('or') ?></span></div>
         <a href="<?= htmlspecialchars($oidcLoginUrl) ?>" class="btn btn-secondary btn-lg">
-            <i class="fas fa-key"></i> <?= htmlspecialchars($oidcName) ?>
+            <i class="fas fa-key" aria-hidden="true"></i> <?= htmlspecialchars($oidcName) ?>
         </a>
     <?php endif; ?>
 
     <?php if ($publicAccess): ?>
-        <div class="auth-links"><a href="index.php" class="back-link"><i class="fas fa-arrow-left"></i> <?= __('login_back') ?></a></div>
+        <div class="auth-links"><a href="index.php" class="back-link"><i class="fas fa-arrow-left" aria-hidden="true"></i> <?= __('login_back') ?></a></div>
     <?php endif; ?>
 </div>
 </section>
diff --git a/login_simple.php b/login_simple.php
index 640ac68..449d11e 100644
--- a/login_simple.php
+++ b/login_simple.php
@@ -166,12 +166,12 @@ try {
         <?php if ($m365Enabled): ?>
             <div class="divider"><span>oder</span></div>
             <a href="<?= htmlspecialchars($m365LoginUrl) ?>" class="btn btn-microsoft">
-                <i class="fab fa-microsoft"></i> Mit Microsoft 365 anmelden
+                <i class="fab fa-microsoft" aria-hidden="true"></i> Mit Microsoft 365 anmelden
             </a>
         <?php endif; ?>
         
         <?php if ($publicAccess): ?>
-            <div class="auth-links"><a href="index.php" class="back-link"><i class="fas fa-arrow-left"></i> Zurück zur Code-Erstellung</a></div>
+            <div class="auth-links"><a href="index.php" class="back-link"><i class="fas fa-arrow-left" aria-hidden="true"></i> Zurück zur Code-Erstellung</a></div>
         <?php endif; ?>
         
         <!-- Debug Info (kann nach erfolgreicher Einrichtung entfernt werden) -->
diff --git a/reset_password.php b/reset_password.php
index 7ec74c7..7f1bc5e 100644
--- a/reset_password.php
+++ b/reset_password.php
@@ -83,7 +83,7 @@ if ($valid && $_SERVER['REQUEST_METHOD'] === 'POST') {
     <?php if ($logoUrl): ?>
         <img src="<?= htmlspecialchars(Ui::mediaUrl($logoUrl)) ?>" alt="Logo" class="logo">
     <?php else: ?>
-        <div class="focus-icon" style="margin-bottom:14px;"><i class="fas fa-key"></i></div>
+        <div class="focus-icon" style="margin-bottom:14px;"><i class="fas fa-key" aria-hidden="true"></i></div>
     <?php endif; ?>
 
     <h1><?= __('reset_new_pw') ?></h1>
diff --git a/updater/templates/update.php b/updater/templates/update.php
index e7a9e7e..1c84369 100644
--- a/updater/templates/update.php
+++ b/updater/templates/update.php
@@ -61,13 +61,13 @@ $channels = \Updater\UpdateManager::CHANNELS;
 <div class="wrap">
     <div class="update-head">
         <div class="title">
-            <span class="focus-icon"><i class="fas fa-rotate"></i></span>
+            <span class="focus-icon"><i class="fas fa-rotate" aria-hidden="true"></i></span>
             <div>
                 <h1 style="font-size:20px;">System-Update</h1>
                 <p class="sub">Aktualisierung aus dem gewählten Release-Channel</p>
             </div>
         </div>
-        <a href="/admin/" class="btn btn-secondary"><i class="fas fa-arrow-left"></i> Administration</a>
+        <a href="/admin/" class="btn btn-secondary"><i class="fas fa-arrow-left" aria-hidden="true"></i> Administration</a>
     </div>
 
     <div class="tabs">
@@ -93,8 +93,8 @@ $channels = \Updater\UpdateManager::CHANNELS;
 
         <div class="card">
             <h2>Updates</h2>
-            <button class="btn btn-primary" id="btnCheck"><i class="fas fa-magnifying-glass"></i> Auf Updates prüfen</button>
-            <button class="btn btn-success" id="btnInstall" style="display:none;margin-left:8px;"><i class="fas fa-download"></i> Update installieren</button>
+            <button class="btn btn-primary" id="btnCheck"><i class="fas fa-magnifying-glass" aria-hidden="true"></i> Auf Updates prüfen</button>
+            <button class="btn btn-success" id="btnInstall" style="display:none;margin-left:8px;"><i class="fas fa-download" aria-hidden="true"></i> Update installieren</button>
 
             <div class="changelog" id="changelog"></div>
 
@@ -150,7 +150,7 @@ $('channel').addEventListener('change', async (e) => {
 // Auf Updates pruefen
 $('btnCheck').addEventListener('click', async () => {
     clearAlerts();
-    $('btnCheck').disabled = true; $('btnCheck').innerHTML = '<i class="fas fa-circle-notch fa-spin"></i> Prüfe …';
+    $('btnCheck').disabled = true; $('btnCheck').innerHTML = '<i class="fas fa-circle-notch fa-spin" aria-hidden="true"></i> Prüfe …';
     try {
         const r = await fetch('update.php?action=check');
         const d = await r.json();
@@ -172,7 +172,7 @@ $('btnCheck').addEventListener('click', async () => {
     } catch (e) {
         showAlert('error', 'Prüfung fehlgeschlagen: ' + e.message);
     } finally {
-        $('btnCheck').disabled = false; $('btnCheck').innerHTML = '<i class="fas fa-magnifying-glass"></i> Auf Updates prüfen';
+        $('btnCheck').disabled = false; $('btnCheck').innerHTML = '<i class="fas fa-magnifying-glass" aria-hidden="true"></i> Auf Updates prüfen';
     }
 });