feat: redesign UI with clean, modern SaaS aesthetic

- Remove excessive animations and gradients
- Implement clean card-based layout
- Add professional progress stepper with checkmarks
- Simplify color scheme to gray/indigo/purple
- Create minimal, elegant component designs
- Add subtle hover effects and transitions
- Improve typography and spacing
- Remove emoji overload, keep minimal icons
- Create professional button styles
- Implement clean form inputs with focus states
- Add proper visual hierarchy
- Simplify loading states and messages
- Create cohesive, modern user experience

frontend/src/components/AudioPlayerSection.tsx

@@ -8,68 +8,47 @@ export default function AudioPlayerSection({
   onDownload
 }: AudioPlayerSectionProps) {
   return (
-    <div className="w-full max-w-4xl mx-auto p-6 sm:p-8 glass-effect rounded-3xl shadow-glow-strong card-hover">
+    <div className="card-modern p-8 space-y-6">
       {/* Success Header */}
-      <div className="text-center mb-8">
-        <div className="inline-block mb-6">
-          <div className="w-24 h-24 sm:w-28 sm:h-28 mx-auto bg-gradient-to-br from-green-400 via-emerald-500 to-teal-600 rounded-3xl shadow-2xl flex items-center justify-center animate-bounce shadow-green-500/50">
-            <span className="text-5xl sm:text-6xl">🎉</span>
-          </div>
+      <div className="text-center">
+        <div className="inline-flex items-center justify-center w-16 h-16 bg-gradient-to-br from-green-400 to-emerald-500 rounded-2xl mb-4">
+          <span className="text-3xl">🎉</span>
         </div>
-        <h2 className="text-3xl sm:text-4xl md:text-5xl font-extrabold gradient-text-animated mb-3">
+        <h2 className="text-3xl font-bold text-gray-900 mb-2">
           Your Audiobook is Ready!
         </h2>
-        <p className="text-gray-700 text-base sm:text-lg font-medium">
+        <p className="text-gray-600">
           Listen below or download to enjoy offline
         </p>
       </div>
       
-      {/* Audio Player Card */}
-      <div className="bg-gradient-to-br from-purple-50 via-indigo-50 to-pink-50 rounded-3xl shadow-2xl p-6 sm:p-10 mb-8 border-2 border-purple-300 hover:shadow-3xl transition-all">
-        <div className="flex items-center gap-4 mb-6">
-          <div className="w-14 h-14 bg-gradient-to-br from-purple-500 via-purple-600 to-indigo-600 rounded-2xl flex items-center justify-center shadow-lg shadow-purple-500/50">
-            <span className="text-2xl">🎧</span>
-          </div>
-          <div>
-            <h3 className="text-xl sm:text-2xl font-extrabold text-gray-800">Listen Now</h3>
-            <p className="text-sm text-gray-600">Your personalized audiobook</p>
-          </div>
-        </div>
-        
+      {/* Audio Player */}
+      <div className="p-6 bg-gradient-to-br from-indigo-50 to-purple-50 rounded-xl border border-indigo-100">
         <audio
           controls
           src={audioUrl}
-          className="w-full min-h-[54px] rounded-2xl shadow-xl"
+          className="w-full"
           preload="metadata"
-          style={{
-            filter: 'drop-shadow(0 8px 16px rgba(0, 0, 0, 0.15))'
-          }}
         >
           Your browser does not support the audio element.
         </audio>
       </div>
 
       {/* Download Button */}
-      <div className="flex justify-center mb-6">
+      <div className="flex justify-center">
         <button
           onClick={onDownload}
-          className="px-12 py-6 min-h-[60px] bg-gradient-to-r from-green-500 via-emerald-600 to-teal-600 hover:from-green-600 hover:via-emerald-700 hover:to-teal-700 text-white font-extrabold rounded-2xl transition-all cursor-pointer touch-manipulation shadow-2xl text-lg sm:text-xl shadow-green-500/50 relative overflow-hidden"
+          className="btn-primary flex items-center gap-2"
         >
-          <span className="flex items-center justify-center gap-4 relative z-10">
-            <span className="text-2xl">⬇️</span>
-            Download Audiobook
-          </span>
+          <span>⬇️</span>
+          Download Audiobook
         </button>
       </div>
 
       {/* Success Message */}
-      <div className="p-6 bg-gradient-to-r from-green-50 via-emerald-50 to-teal-50 border-2 border-green-300 text-green-900 rounded-2xl shadow-lg text-center text-sm sm:text-base">
-        <div className="flex items-center justify-center gap-3 mb-2">
-          <span className="text-3xl">✅</span>
-          <p className="font-extrabold text-lg">Success!</p>
-        </div>
+      <div className="p-4 bg-green-50 border border-green-200 text-green-800 rounded-xl text-center">
         <p className="font-medium">
-          Your audiobook has been successfully generated with AI-powered voices!
+          ✅ Your audiobook has been successfully generated!
         </p>
       </div>
     </div>