fix(lyrics): disable karaoke gradient in immersive, increase font +2pt

- Font size: 28px inactive, 30px active
- Disabled background-clip karaoke effect in immersive mode
- Active line now pure white (#ffffff)
- Past lines dimmed to 35% opacity

src/lib/components/lyrics/LyricsLines.svelte

@@ -192,7 +192,7 @@
 
   .lyrics-lines.immersive .lyrics-line {
     font-family: 'Oswald', var(--font-sans), sans-serif;
-    font-size: 26px;
+    font-size: 28px;
     font-weight: 400;
     letter-spacing: 0.02em;
     /* Text shadow for contrast against any background */
@@ -202,12 +202,26 @@
   }
 
   .lyrics-lines.immersive .lyrics-line.active {
-    font-size: 28px;
+    font-size: 30px;
     font-weight: 600;
-    color: #ffffff;
+    color: #ffffff !important;
     opacity: 1;
   }
 
+  /* Disable karaoke gradient in immersive - keep text bright white */
+  .lyrics-lines.immersive .lyrics-line.active .line-text {
+    background: none !important;
+    -webkit-background-clip: unset !important;
+    background-clip: unset !important;
+    color: #ffffff !important;
+  }
+
+  /* Past lines in immersive should be clearly dimmer than active */
+  .lyrics-lines.immersive .lyrics-line.past {
+    color: rgba(255, 255, 255, 0.35);
+    font-weight: 400;
+  }
+
   .lyrics-line {
     color: var(--text-secondary);
     font-family: var(--font-sans);