diff --git a/app/templates/_icons.html b/app/templates/_icons.html
index cb8ad39..e3c0373 100644
--- a/app/templates/_icons.html
+++ b/app/templates/_icons.html
@@ -49,3 +49,31 @@
 {% macro spinner(size=16) -%}
 {{ base('<path d="M21 12a9 9 0 1 1-6.219-8.56"/>', size) }}
 {%- endmacro %}
+
+{% macro sun(size=16) -%}
+{{ base('<circle cx="12" cy="12" r="4"/><path d="M12 2v2"/><path d="M12 20v2"/><path d="m4.93 4.93 1.41 1.41"/><path d="m17.66 17.66 1.41 1.41"/><path d="M2 12h2"/><path d="M20 12h2"/><path d="m6.34 17.66-1.41 1.41"/><path d="m19.07 4.93-1.41 1.41"/>', size) }}
+{%- endmacro %}
+
+{% macro moon(size=16) -%}
+{{ base('<path d="M12 3a6 6 0 0 0 9 9 9 9 0 1 1-9-9Z"/>', size) }}
+{%- endmacro %}
+
+{% macro menu(size=16) -%}
+{{ base('<line x1="4" x2="20" y1="6" y2="6"/><line x1="4" x2="20" y1="12" y2="12"/><line x1="4" x2="20" y1="18" y2="18"/>', size) }}
+{%- endmacro %}
+
+{% macro user(size=16) -%}
+{{ base('<circle cx="12" cy="12" r="10"/><circle cx="12" cy="10" r="3"/><path d="M7 20.662V19a2 2 0 0 1 2-2h6a2 2 0 0 1 2 2v1.662"/>', size) }}
+{%- endmacro %}
+
+{% macro log_out(size=16) -%}
+{{ base('<path d="M9 21H5a2 2 0 0 1-2-2V5a2 2 0 0 1 2-2h4"/><polyline points="16 17 21 12 16 7"/><line x1="21" x2="9" y1="12" y2="12"/>', size) }}
+{%- endmacro %}
+
+{% macro sliders(size=16) -%}
+{{ base('<line x1="21" x2="14" y1="4" y2="4"/><line x1="10" x2="3" y1="4" y2="4"/><line x1="21" x2="12" y1="12" y2="12"/><line x1="8" x2="3" y1="12" y2="12"/><line x1="21" x2="16" y1="20" y2="20"/><line x1="12" x2="3" y1="20" y2="20"/><line x1="14" x2="14" y1="2" y2="6"/><line x1="8" x2="8" y1="10" y2="14"/><line x1="16" x2="16" y1="18" y2="22"/>', size) }}
+{%- endmacro %}
+
+{% macro tag(size=16) -%}
+{{ base('<path d="M12.586 2.586A2 2 0 0 0 11.172 2H4a2 2 0 0 0-2 2v7.172a2 2 0 0 0 .586 1.414l8.704 8.704a2.426 2.426 0 0 0 3.42 0l6.58-6.58a2.426 2.426 0 0 0 0-3.42z"/><circle cx="7.5" cy="7.5" r="1.5"/>', size) }}
+{%- endmacro %}
diff --git a/app/templates/base.html b/app/templates/base.html
index 33aa95c..0abdd11 100644
--- a/app/templates/base.html
+++ b/app/templates/base.html
@@ -4,13 +4,34 @@
   <meta charset="utf-8">
   <meta name="viewport" content="width=device-width, initial-scale=1">
   <title>{% block title %}LinkVault{% endblock %}</title>
+  <script>
+    /* Theme so früh wie möglich setzen, damit die Seite nicht kurz hell aufblitzt. */
+    (function () {
+      try {
+        var stored = localStorage.getItem('linkvault-theme');
+        if (stored === 'light' || stored === 'dark') {
+          document.documentElement.setAttribute('data-theme', stored);
+        } else if (window.matchMedia && window.matchMedia('(prefers-color-scheme: light)').matches) {
+          document.documentElement.setAttribute('data-theme', 'light');
+        }
+      } catch (e) {}
+    })();
+  </script>
   <script src="https://unpkg.com/htmx.org@2.0.3"></script>
   <style>
     :root {
+      color-scheme: dark;
       --bg: #0f172a; --panel: #1e293b; --panel2: #273449;
       --text: #e2e8f0; --muted: #94a3b8; --accent: #6366f1;
       --accent-hover: #818cf8; --border: #334155; --danger: #ef4444;
     }
+    :root[data-theme="light"] {
+      color-scheme: light;
+      --bg: #f8fafc; --panel: #ffffff; --panel2: #f1f5f9;
+      --text: #0f172a; --muted: #64748b; --accent: #6366f1;
+      --accent-hover: #4f46e5; --border: #e2e8f0; --danger: #dc2626;
+    }
+    body { transition: background-color .15s, color .15s; }
     * { box-sizing: border-box; }
     body {
       margin: 0; font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
@@ -136,6 +157,7 @@
       display: inline-flex; align-items: center; justify-content: center;
       width: 30px; height: 30px; padding: 0;
     }
+    .theme-icon-dark, .theme-icon-light { display: inline-flex; }
     .icon-warn { color: #eab308; }
     .icon-bookmark-active { color: #eab308; }
 
@@ -149,6 +171,30 @@
       text-align: center; padding: 16px 24px; margin-top: 24px;
       color: var(--muted); font-size: .8rem; border-top: 1px solid var(--border);
     }
+
+    .user-menu { position: relative; display: flex; align-items: center; gap: 4px; }
+    .user-dropdown {
+      position: absolute; top: calc(100% + 8px); right: 0; min-width: 230px;
+      background: var(--panel); border: 1px solid var(--border); border-radius: 10px;
+      box-shadow: 0 12px 32px rgba(0,0,0,.35); padding: 6px; z-index: 50;
+    }
+    :root[data-theme="light"] .user-dropdown { box-shadow: 0 12px 32px rgba(15,23,42,.14); }
+    .dropdown-email {
+      padding: 8px 10px; font-size: .8rem; color: var(--muted);
+      word-break: break-all;
+    }
+    .dropdown-sep { height: 1px; background: var(--border); margin: 4px 0; }
+    .dropdown-item {
+      display: flex; align-items: center; gap: 8px; width: 100%; text-align: left;
+      background: transparent; color: var(--text); border: none; border-radius: 6px;
+      padding: 8px 10px; font-size: .875rem; font-weight: 400; cursor: pointer;
+    }
+    .dropdown-item:hover:not(:disabled) { background: var(--panel2); }
+    .dropdown-item:disabled { color: var(--muted); cursor: default; opacity: .65; }
+    .dropdown-item .soon {
+      margin-left: auto; font-size: .65rem; text-transform: uppercase; letter-spacing: .04em;
+      background: var(--panel2); color: var(--muted); padding: 2px 6px; border-radius: 99px;
+    }
   </style>
 </head>
 <body>
@@ -156,5 +202,49 @@
   <footer class="app-footer">
     &copy; {{ app_author }} &middot; Version {{ app_version }} &middot; {{ app_host }}
   </footer>
+
+  <script>
+    (function () {
+      var themeBtn = document.getElementById('theme-toggle');
+      if (themeBtn) {
+        var dark = themeBtn.querySelector('.theme-icon-dark');
+        var light = themeBtn.querySelector('.theme-icon-light');
+        var applyIcon = function (theme) {
+          dark.style.display = theme === 'light' ? 'none' : 'inline-flex';
+          light.style.display = theme === 'light' ? 'inline-flex' : 'none';
+        };
+        applyIcon(document.documentElement.getAttribute('data-theme') === 'light' ? 'light' : 'dark');
+        themeBtn.addEventListener('click', function () {
+          var next = document.documentElement.getAttribute('data-theme') === 'light' ? 'dark' : 'light';
+          document.documentElement.setAttribute('data-theme', next);
+          try { localStorage.setItem('linkvault-theme', next); } catch (e) {}
+          applyIcon(next);
+        });
+      }
+
+      var menuBtn = document.getElementById('menu-toggle');
+      var dropdown = document.getElementById('user-dropdown');
+      if (menuBtn && dropdown) {
+        var close = function () {
+          dropdown.hidden = true;
+          menuBtn.setAttribute('aria-expanded', 'false');
+        };
+        var open = function () {
+          dropdown.hidden = false;
+          menuBtn.setAttribute('aria-expanded', 'true');
+        };
+        menuBtn.addEventListener('click', function (e) {
+          e.stopPropagation();
+          if (dropdown.hidden) open(); else close();
+        });
+        document.addEventListener('click', function (e) {
+          if (!dropdown.hidden && !dropdown.contains(e.target) && e.target !== menuBtn) close();
+        });
+        document.addEventListener('keydown', function (e) {
+          if (e.key === 'Escape') close();
+        });
+      }
+    })();
+  </script>
 </body>
 </html>
diff --git a/app/templates/index.html b/app/templates/index.html
index 8a68662..33effd1 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -10,10 +10,32 @@
       {{ icons.alert(size=14) }} KI aus
     </span>
     {% endif %}
-    <span>{{ user.email }}</span>
-    <form method="post" action="/logout" style="margin:0;">
-      <button class="ghost" type="submit">Abmelden</button>
-    </form>
+
+    <button id="theme-toggle" type="button" class="ghost icon-btn" title="Farbschema wechseln">
+      <span class="theme-icon-dark">{{ icons.moon() }}</span>
+      <span class="theme-icon-light">{{ icons.sun() }}</span>
+    </button>
+
+    <div class="user-menu">
+      <button type="button" class="ghost icon-btn" title="{{ user.email }}">{{ icons.user() }}</button>
+      <button id="menu-toggle" type="button" class="ghost icon-btn" title="Menü"
+              aria-haspopup="true" aria-expanded="false">{{ icons.menu() }}</button>
+
+      <div id="user-dropdown" class="user-dropdown" hidden>
+        <div class="dropdown-email">{{ user.email }}</div>
+        <div class="dropdown-sep"></div>
+        <button type="button" class="dropdown-item" disabled>
+          {{ icons.tag(size=15) }} Tags verwalten <span class="soon">bald</span>
+        </button>
+        <button type="button" class="dropdown-item" disabled>
+          {{ icons.sliders(size=15) }} Einstellungen <span class="soon">bald</span>
+        </button>
+        <div class="dropdown-sep"></div>
+        <form method="post" action="/logout" style="margin:0;">
+          <button type="submit" class="dropdown-item">{{ icons.log_out(size=15) }} Abmelden</button>
+        </form>
+      </div>
+    </div>
   </div>
 </header>