feat: dynamic NP cover color, taller settings modal, fix Android song sync

- Now Playing: add "Dynamische Hintergrundfarbe" toggle in Theme settings;
  when on, np-bg uses higher saturation/brightness so the cover color really
  shows through the blurred background
- Settings modal: extend to bottom nav on mobile (was leaving ~74px dead space
  for the player bar which the overlay already covers at z-index 200)
- Android: fix onTrackChanged always staying on the first song — the snapshot
  from MediaController can lag behind ExoPlayer on auto-advance, causing the
  stale currentIndex to overwrite the correct p.index; now only advance to
  a higher live index (for rapid-skip catch-up) and use p.trackId directly
  instead of the potentially-stale snapshot id for the queue-mismatch guard

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

index.html

@@ -663,6 +663,13 @@
           Theme
         </h3>
         <div id="theme-picker" class="theme-picker"></div>
+        <div class="edit-pl-toggle-row" style="margin-top:14px">
+          <div>
+            <span>Dynamische Hintergrundfarbe</span>
+            <div class="hint" style="margin-top:2px">Jetzt-Läuft-Hintergrund nach Cover-Hauptfarbe</div>
+          </div>
+          <div id="s-cover-color-bg" class="toggle" onclick="this.classList.toggle('on')"></div>
+        </div>
       </div>
     </div>
     <!-- Sticky footer -->

src/main.js

@@ -9,7 +9,7 @@ import {
   initProgressScrub, updateProgress, updatePreviewProgress, stopPreview,
   toggleRadioMode, starCurrent, downloadCurrent, renderQueue, playPreview,
   toggleStar, dlSongLocal, _applyRadioBtn, _applyShuffleRepeat, _restoreLastPlayed, setPlayIcon,
-  npToggleStar, updateMediaSession,
+  npToggleStar, updateMediaSession, updateNpColorMode,
 } from './player.js';
 import {
   navigate, _navGoBack, _navLoad, onHeaderSearch, closeHeaderSearch,
@@ -125,6 +125,7 @@ window.addEventListener('load', () => {
     S.cfg = JSON.parse(saved);
     if(!S.cfg.backendUrl && window.NS_BACKEND_URL?.trim()) S.cfg.backendUrl = window.NS_BACKEND_URL.trim().replace(/\/$/,'');
     startApp();
+    updateNpColorMode();
   }
   if(window.NS_SERVER_URL?.trim()) { const el=document.getElementById('srv-url'); if(el&&!el.value) el.value=window.NS_SERVER_URL.trim(); }
 

src/player.js

@@ -184,20 +184,20 @@ window.NSPlayer = {
     try {
       const p = JSON.parse(payloadJson);
       if (typeof p.index !== 'number') return;
-      // Reconcile with the live native state so stale out-of-order callbacks
-      // (e.g. from rapid skips) don't overwrite the already-correct index.
+      // p.index comes directly from ExoPlayer (always accurate).
+      // Only advance to a higher live index to handle rapid forward skips where
+      // the callback can arrive before we processed the previous one.
+      // Never let a stale MediaController snapshot pull us BACK to an old index.
       let idx = p.index;
-      let liveId = '';
       try {
         const live = JSON.parse(window.NSBridge.getState() || '{}');
-        if (typeof live.currentIndex === 'number') idx = live.currentIndex;
-        liveId = live.currentId || '';
+        if (typeof live.currentIndex === 'number' && live.currentIndex > idx) idx = live.currentIndex;
       } catch {}
       if (idx < 0 || idx >= S.queue.length) return;
-      // Reject stale callbacks from the old queue: if the song ID at this index
-      // doesn't match what native is actually playing, the queues are mismatched.
-      // Allow through if reason='queue' (we triggered a setQueue) or if no IDs to compare.
-      if (liveId && S.queue[idx]?.id && String(liveId) !== String(S.queue[idx].id) && p.reason !== 'queue') return;
+      // Verify using the trackId from the callback payload (ExoPlayer-direct, not the
+      // potentially-stale snapshot) so auto-advance is never rejected by a lagged snapshot.
+      const trackId = p.trackId || '';
+      if (trackId && S.queue[idx]?.id && String(trackId) !== String(S.queue[idx].id) && p.reason !== 'queue') return;
       const indexChanged = (idx !== S.qIdx);
       S.qIdx = idx;
       const s = S.queue[S.qIdx];
@@ -484,6 +484,11 @@ export function updatePlayerUI(s, _skipMediaSession = false) {
   if (_npCv && _npCv !== _npBgLastUrl) { const _pre = new Image(); _pre.src = _npCv; }
 }
 
+// Apply/remove dynamic-color mode based on current setting.
+export function updateNpColorMode() {
+  document.getElementById('np-overlay')?.classList.toggle('dynamic-color', !!S.cfg?.coverColorBg);
+}
+
 let _npBgCurr = 'a';
 let _npBgLastUrl = '';
 function _crossfadeNpBg(cv) {

src/ui.js

@@ -3,7 +3,7 @@ import { esc, formatDur, toast } from './utils.js';
 import { api, coverUrl, ndAuth, fetchRomajiIndex, romajiConvert, romajiLookup, invalidateRomajiIndex, invalidateCoverCache } from './api.js';
 import { THEMES, applyTheme, getCurrentThemeId } from './themes.js';
 // Circular imports — safe (only used inside function bodies)
-import { playQueue, dlSongLocal, toggleStar, togglePlay, renderQueue, syncNpStar, updateStarBtn, npToggleStar, playCurrent, _syncNpDirect, setPlayIcon, nativeInsertAt, refreshDisplayMode } from './player.js';
+import { playQueue, dlSongLocal, toggleStar, togglePlay, renderQueue, syncNpStar, updateStarBtn, npToggleStar, playCurrent, _syncNpDirect, setPlayIcon, nativeInsertAt, refreshDisplayMode, updateNpColorMode } from './player.js';
 import { navigate, loadPlaylists } from './views.js';
 
 // ─── SIDEBAR ───
@@ -49,6 +49,7 @@ export function openSettings() {
   document.getElementById('s-backend').value      = S.cfg.backendUrl       || '';
   document.getElementById('s-show-playcount').classList.toggle('on', !!S.cfg.showPlayCount);
   document.getElementById('s-show-romaji').classList.toggle('on', !!S.cfg.showRomaji);
+  document.getElementById('s-cover-color-bg').classList.toggle('on', !!S.cfg.coverColorBg);
   _renderThemePicker();
   document.getElementById('settings-modal').classList.add('open');
   checkBackend();
@@ -86,6 +87,8 @@ export function saveSettings() {
   S.cfg.showPlayCount  = document.getElementById('s-show-playcount').classList.contains('on');
   const romajiChanged  = S.cfg.showRomaji !== document.getElementById('s-show-romaji').classList.contains('on');
   S.cfg.showRomaji     = document.getElementById('s-show-romaji').classList.contains('on');
+  S.cfg.coverColorBg   = document.getElementById('s-cover-color-bg').classList.contains('on');
+  updateNpColorMode();
   localStorage.setItem('ns_cfg', JSON.stringify(S.cfg));
   closeSettings(); toast('✅ Gespeichert');
   if (romajiChanged) {

styles.css

@@ -563,7 +563,7 @@ button:focus{outline:none}
   .toast-container{bottom:calc(var(--player-h) + 80px + 16px)}
   .jobs-panel{bottom:calc(var(--player-h) + 80px + 16px)}
   .bnav-item{padding:6px 2px;box-sizing:border-box}
-  #settings-modal{align-items:flex-start;padding-top:max(env(safe-area-inset-top),16px);padding-bottom:calc(var(--player-h) + 80px + env(safe-area-inset-bottom) + 8px)}
+  #settings-modal{align-items:flex-start;padding-top:max(env(safe-area-inset-top),16px);padding-bottom:calc(80px + env(safe-area-inset-bottom))}
   #settings-modal .modal{max-height:100%!important;overflow:hidden}
 }
 
@@ -590,6 +590,10 @@ button:focus{outline:none}
   will-change:opacity;
   z-index:0;
 }
+/* Dynamic cover color mode: more vivid/saturated background */
+.np-overlay.dynamic-color .np-bg{
+  filter:blur(60px) brightness(.5) saturate(3);
+}
 
 .np-inner{
   position:relative;z-index:1;