diff --git a/src/components/LibraryApp.tsx b/src/components/LibraryApp.tsx
index 38d4053..681f665 100644
--- a/src/components/LibraryApp.tsx
+++ b/src/components/LibraryApp.tsx
@@ -112,11 +112,14 @@ function LibStyles() {
     .hidden{display:none;}
     .leer{padding:60px 24px;text-align:center;display:flex;flex-direction:column;align-items:center;gap:10px;}
     .leer h3{margin:0;font-size:17px;}.leer p{margin:0;color:var(--soft);max-width:38ch;}
-    .galerie{display:grid;grid-template-columns:repeat(auto-fill,minmax(190px,1fr));gap:14px;}
-    .kachel{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:9px;}
+    .galerie{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:12px;align-items:start;}
+    @media(min-width:768px){.galerie{grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:14px;}}
+    .kachel{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:8px;}
     .kachel.gewaehlt{border-color:var(--accent);box-shadow:0 0 0 1px var(--accent);}
-    .kachel-bild{position:relative;aspect-ratio:1;background:var(--paper);border-radius:2px;overflow:hidden;cursor:pointer;}
-    .kachel-bild img{width:100%;height:100%;object-fit:cover;display:block;}
+    .kachel-bild{position:relative;border-radius:3px;overflow:hidden;cursor:pointer;
+      background:repeating-conic-gradient(oklch(90% 0.006 95) 0% 25%, oklch(96% 0.004 95) 0% 50%) 50%/16px 16px;}
+    .kachel-bild img{width:100%;height:auto;display:block;transition:transform .12s;}
+    .kachel-bild:active img{transform:scale(.98);}
     .haken{position:absolute;top:6px;left:6px;width:21px;height:21px;border-radius:50%;border:1.5px solid #fff;background:rgba(22,21,15,.35);color:#fff;display:flex;align-items:center;justify-content:center;font-size:12px;}
     .kachel.gewaehlt .haken{background:var(--accent);}
     .name{margin-top:8px;width:100%;font-size:12.5px;padding:6px 8px;font-family:var(--font-mono);border:1px solid var(--line);border-radius:3px;background:#fff;}
diff --git a/src/components/QueueApp.tsx b/src/components/QueueApp.tsx
index 5f1305b..4cac8b0 100644
--- a/src/components/QueueApp.tsx
+++ b/src/components/QueueApp.tsx
@@ -110,8 +110,9 @@ function QStyles() {
     .fein.err{color:var(--err);}
     .items{display:flex;flex-direction:column;}
     .item{display:flex;align-items:center;gap:12px;padding:10px 16px;border-bottom:1px solid var(--line);}
-    .thumb{width:44px;height:44px;flex:none;background:var(--paper);border:1px solid var(--line);border-radius:3px;overflow:hidden;display:flex;align-items:center;justify-content:center;}
-    .thumb img{width:100%;height:100%;object-fit:cover;}
+    .thumb{width:46px;height:46px;flex:none;border:1px solid var(--line);border-radius:3px;overflow:hidden;display:flex;align-items:center;justify-content:center;
+      background:repeating-conic-gradient(oklch(90% 0.006 95) 0% 25%, oklch(96% 0.004 95) 0% 50%) 50%/12px 12px;}
+    .thumb img{width:100%;height:100%;object-fit:contain;}
     .itxt{flex:1;min-width:0;}
     .itxt b{font-size:13.5px;display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;}
     .iact{flex:none;}
diff --git a/src/components/StudioApp.tsx b/src/components/StudioApp.tsx
index 1e57c8a..0e3d542 100644
--- a/src/components/StudioApp.tsx
+++ b/src/components/StudioApp.tsx
@@ -273,10 +273,11 @@ function StudioStyles() {
     .drop.drag{border-color:var(--accent);background:var(--accent-bg);}
     .drop p{margin:0;color:var(--soft);font-size:14px;line-height:1.55;}
     .kbd{font-family:var(--font-mono);font-size:12px;background:var(--paper);border:1px solid var(--line);border-radius:3px;padding:1px 6px;}
-    .mini-raster{display:grid;grid-template-columns:repeat(auto-fill,minmax(78px,1fr));gap:8px;width:100%;}
-    .mini-bild{position:relative;aspect-ratio:3/4;background:var(--paper);border:1px solid var(--line);border-radius:3px;overflow:hidden;}
+    .mini-raster{display:grid;grid-template-columns:repeat(auto-fill,minmax(84px,1fr));gap:8px;width:100%;}
+    .mini-bild{position:relative;aspect-ratio:1;border:1px solid var(--line);border-radius:3px;overflow:hidden;
+      background:repeating-conic-gradient(oklch(90% 0.006 95) 0% 25%, oklch(96% 0.004 95) 0% 50%) 50%/14px 14px;}
     .mini-bild.err{border-color:var(--err);}
-    .mini-bild img{width:100%;height:100%;object-fit:cover;display:block;}
+    .mini-bild img{width:100%;height:100%;object-fit:contain;display:block;}
     .mini-bild>button{position:absolute;top:3px;right:3px;width:20px;height:20px;border:none;border-radius:50%;background:rgba(22,21,15,.75);color:#fff;cursor:pointer;font-size:14px;line-height:1;}
     .mini-bild .badge{position:absolute;bottom:3px;left:3px;background:var(--err);color:#fff;width:18px;height:18px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:700;}
     .lade{position:absolute;inset:0;background:var(--paper);opacity:.6;}
diff --git a/src/layouts/Base.astro b/src/layouts/Base.astro
index 71fe977..9e9130f 100644
--- a/src/layouts/Base.astro
+++ b/src/layouts/Base.astro
@@ -8,50 +8,114 @@ import '../styles/tokens.css';
 interface Props { title?: string }
 const { title = 'Klarbild' } = Astro.props;
 const user = Astro.locals.user;
+const path = Astro.url.pathname;
+const active = (href: string) => href === '/' ? path === '/' : path.startsWith(href);
+
+const nav = [
+  { href: '/', label: 'Studio', icon: 'studio' },
+  { href: '/bibliothek', label: 'Bibliothek', icon: 'library' },
+  { href: '/warteschlange', label: 'Warteschlange', icon: 'queue' },
+  ...(user?.role === 'admin' ? [{ href: '/admin', label: 'Admin', icon: 'admin' }] : []),
+];
+
+const S = 'fill="none" stroke="currentColor" stroke-width="1.75" stroke-linecap="round" stroke-linejoin="round"';
+const ICONS: Record<string, string> = {
+  studio: `<svg viewBox="0 0 24 24" ${S}><rect x="3.5" y="3.5" width="17" height="17" rx="4"/><path d="M12 8.5v7M8.5 12h7"/></svg>`,
+  library: `<svg viewBox="0 0 24 24" ${S}><rect x="3.5" y="3.5" width="7" height="7" rx="1.5"/><rect x="13.5" y="3.5" width="7" height="7" rx="1.5"/><rect x="3.5" y="13.5" width="7" height="7" rx="1.5"/><rect x="13.5" y="13.5" width="7" height="7" rx="1.5"/></svg>`,
+  queue: `<svg viewBox="0 0 24 24" ${S}><path d="M9 6h11M9 12h11M9 18h7"/><circle cx="4.5" cy="6" r="1.15" fill="currentColor" stroke="none"/><circle cx="4.5" cy="12" r="1.15" fill="currentColor" stroke="none"/><circle cx="4.5" cy="18" r="1.15" fill="currentColor" stroke="none"/></svg>`,
+  admin: `<svg viewBox="0 0 24 24" ${S}><path d="M4 8h9M17 8h3M4 16h3M11 16h9"/><circle cx="15" cy="8" r="2.2"/><circle cx="9" cy="16" r="2.2"/></svg>`,
+};
 ---
 <!doctype html>
 <html lang="de">
   <head>
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1, viewport-fit=cover" />
-    <meta name="theme-color" content="#0e5f6e" />
+    <meta name="theme-color" content="#EAEAE3" />
     <title>{title}</title>
   </head>
   <body>
     {user && (
       <header class="topbar">
         <a href="/" class="brand"><span class="regmark"></span>klarbild</a>
-        <nav>
-          <a href="/">Studio</a>
-          <a href="/bibliothek">Bibliothek</a>
-          <a href="/warteschlange">Warteschlange</a>
-          {user.role === 'admin' && <a href="/admin">Admin</a>}
+        <nav class="topnav">
+          {nav.map((n) => (
+            <a href={n.href} class:list={['tnav', { on: active(n.href) }]}>{n.label}</a>
+          ))}
         </nav>
         <form method="post" action="/api/auth/logout" class="logout">
-          <span>{user.name}</span>
-          <button type="submit">Abmelden</button>
+          <span class="uname">{user.name}</span>
+          <button type="submit" aria-label="Abmelden">Abmelden</button>
         </form>
       </header>
     )}
+
     <main class="wrap"><slot /></main>
+
+    {user && (
+      <nav class="tabbar" aria-label="Hauptnavigation">
+        {nav.map((n) => (
+          <a href={n.href} class:list={['tab', { on: active(n.href) }]}>
+            <span class="ticon" set:html={ICONS[n.icon]} />
+            <span class="tlabel">{n.label}</span>
+          </a>
+        ))}
+      </nav>
+    )}
+
     <style is:global>
-      .wrap { max-width: var(--maxw); margin: 0 auto; padding: 24px 20px 80px; }
+      .wrap { max-width: var(--maxw); margin: 0 auto; padding: 20px 16px calc(88px + env(safe-area-inset-bottom)); }
+      @media (min-width: 768px) { .wrap { padding: 26px 22px 80px; } }
+
+      /* Top bar */
       .topbar {
-        display: flex; align-items: center; gap: 20px;
-        padding: 12px 20px; border-bottom: 1px solid var(--line);
-        background: var(--surface); position: sticky; top: 0; z-index: 10;
+        display: flex; align-items: center; gap: 14px;
+        padding: 10px 16px; border-bottom: 1px solid var(--line);
+        background: color-mix(in oklab, var(--card) 88%, transparent);
+        backdrop-filter: saturate(1.2) blur(8px);
+        position: sticky; top: 0; z-index: 20;
+        padding-top: calc(10px + env(safe-area-inset-top));
       }
       .brand { display: inline-flex; align-items: center; gap: 8px;
-        font-family: var(--font-display); font-weight: 700; font-size: 1.3rem;
+        font-family: var(--font-display); font-weight: 700; font-size: 1.2rem;
         color: var(--ink); text-decoration: none; letter-spacing: -0.02em; }
       .brand .regmark { transform: translateY(1px); }
-      .topbar nav { display: flex; gap: 16px; margin-left: 8px; }
-      .topbar nav a { color: var(--ink-soft); text-decoration: none; font-size: 0.95rem; }
-      .topbar nav a:hover { color: var(--ink); }
-      .logout { margin-left: auto; display: flex; align-items: center; gap: 10px;
-        color: var(--ink-mute); font-size: 0.9rem; }
+      .topnav { display: none; }
+      @media (min-width: 768px) {
+        .topnav { display: flex; gap: 4px; margin-left: 8px; }
+        .tnav { padding: 7px 12px; border-radius: 999px; color: var(--ink-soft);
+          text-decoration: none; font-size: 0.92rem; transition: background .15s, color .15s; }
+        .tnav:hover { color: var(--ink); background: var(--surface-2, var(--paper)); }
+        .tnav.on { color: var(--accent); background: var(--accent-bg); font-weight: 600; }
+      }
+      .logout { margin-left: auto; display: flex; align-items: center; gap: 10px; }
+      .uname { color: var(--ink-mute, var(--soft)); font-size: 0.9rem; display: none; }
+      @media (min-width: 480px) { .uname { display: inline; } }
       .logout button { background: none; border: 1px solid var(--line); border-radius: 999px;
-        padding: 5px 12px; color: var(--ink-soft); cursor: pointer; }
+        padding: 7px 14px; color: var(--ink-soft); cursor: pointer; font-family: inherit; font-size: 0.85rem;
+        transition: transform .06s ease, background .15s; min-height: 36px; }
+      .logout button:active { transform: scale(0.96); }
+
+      /* Bottom tab bar (mobile-first) */
+      .tabbar {
+        position: fixed; left: 0; right: 0; bottom: 0; z-index: 30;
+        display: grid; grid-auto-flow: column; grid-auto-columns: 1fr;
+        background: color-mix(in oklab, var(--card) 92%, transparent);
+        backdrop-filter: saturate(1.3) blur(12px);
+        border-top: 1px solid var(--line);
+        padding-bottom: env(safe-area-inset-bottom);
+      }
+      .tab { display: flex; flex-direction: column; align-items: center; gap: 3px;
+        padding: 9px 4px 8px; text-decoration: none; color: var(--ink-mute, var(--soft));
+        font-size: 10.5px; letter-spacing: .01em; transition: color .15s, transform .06s; }
+      .tab:active { transform: scale(0.94); }
+      .tab.on { color: var(--accent); }
+      .tab .ticon { width: 22px; height: 22px; display: grid; place-items: center; }
+      .tab .ticon svg { width: 22px; height: 22px; }
+      .tlabel { line-height: 1; }
+      @media (min-width: 768px) { .tabbar { display: none; } }
+
+      :focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
     </style>
   </body>
 </html>
diff --git a/src/styles/tokens.css b/src/styles/tokens.css
index b0109cf..d836da6 100644
--- a/src/styles/tokens.css
+++ b/src/styles/tokens.css
@@ -56,6 +56,14 @@ a { color: var(--accent); }
 .regmark::before { left: 50%; top: 0; width: 1.5px; height: 100%; transform: translateX(-50%); }
 .regmark::after { top: 50%; left: 0; height: 1.5px; width: 100%; transform: translateY(-50%); }
 
+/* Mobile-First: 16px-Felder gegen iOS-Zoom beim Fokus */
+@media (max-width: 767px) {
+  input, select, textarea { font-size: 16px !important; }
+}
+/* Taktiles Feedback auf allen Buttons */
+button { transition: transform 0.06s ease; }
+button:active { transform: scale(0.97); }
+
 @media (prefers-reduced-motion: reduce) {
   * { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; }
 }