Design: neutrale Grau-Hintergründe, Kapitelliste volle Höhe

- Hintergrundfarben auf neutrales Dunkelgrau geändert (#111111/#1a1a1a/#222222)
- Nur Akzentfarbe (#1ed760) und Buttons/aktive States bleiben grün
- ChapterList: max-h-64 entfernt, nutzt jetzt volle Seitenhöhe

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/components/player/ChapterList.tsx

@@ -23,7 +23,7 @@ export default function ChapterList({ chapters, currentTime, onSeek }: Props) {
   }
 
   return (
-    <div className="mt-4 border-t border-divider pt-4 max-h-64 overflow-y-auto">
+    <div className="mt-4 border-t border-divider pt-4">
       <p className="text-muted uppercase tracking-wider mb-2" style={{ fontSize: '10px', fontWeight: 600, letterSpacing: '0.12em' }}>Kapitel</p>
       {chapters.map((ch, i) => (
         <button

frontend/src/index.css

@@ -3,16 +3,16 @@
 @tailwind utilities;
 
 body {
-  background: #0a0d0b;
-  color: #e4ede5;
+  background: #111111;
+  color: #e8e8e8;
   font-family: 'Inter', sans-serif;
   font-size: 14px;
 }
 
 ::-webkit-scrollbar { width: 6px; height: 6px; }
 ::-webkit-scrollbar-track { background: transparent; }
-::-webkit-scrollbar-thumb { background: #2e3f30; border-radius: 3px; }
-::-webkit-scrollbar-thumb:hover { background: #3d5440; }
+::-webkit-scrollbar-thumb { background: #333333; border-radius: 3px; }
+::-webkit-scrollbar-thumb:hover { background: #444444; }
 
 input[type=range] {
   -webkit-appearance: none;

frontend/tailwind.config.js

@@ -5,15 +5,15 @@ export default {
   theme: {
     extend: {
       colors: {
-        background: '#0a0d0b',
-        surface: '#111511',
-        card: '#161d17',
-        divider: '#1e2a1f',
+        background: '#111111',
+        surface: '#1a1a1a',
+        card: '#222222',
+        divider: '#303030',
         primary: '#1ed760',
-        'primary-dim': '#155a2a',
-        ink: '#e4ede5',
-        muted: '#6a8c6d',
-        muted2: '#2e3f30',
+        'primary-dim': '#1a3d28',
+        ink: '#e8e8e8',
+        muted: '#888888',
+        muted2: '#333333',
         c1: '#1a2e1c',
         c2: '#1c1a2e',
         c3: '#2e1a1a',