diff --git a/README.md b/README.md
index 56d695a..80ea669 100644
--- a/README.md
+++ b/README.md
@@ -311,6 +311,10 @@ Then put it behind your existing reverse proxy like everything else
       real fullscreen toggle — fullscreen now targets the whole player,
       not just the `<video>`, so the request buttons stay visible — see
       docs/architecture.md
+- [x] Retired the browser's native `<video controls>` (it was rendering
+      as its own always-on-top bar, duplicating the cast icon and
+      overlapping the new bottom bar in fullscreen) in favor of fully
+      custom play/pause, a seek bar, and mute — see docs/architecture.md
 - [ ] Try a full party end-to-end with two real accounts (still the main gap)
 - [ ] Try casting to a real Chromecast (only the SDK's own bootstrap is
       confirmed here — no real device/session)
diff --git a/client/src/cast.ts b/client/src/cast.ts
index 1493396..a238de1 100644
--- a/client/src/cast.ts
+++ b/client/src/cast.ts
@@ -16,6 +16,10 @@
 export interface PlaybackDriver {
   currentTime: number;
   readonly paused: boolean;
+  /** 0 until known (matches <video>'s own `duration` before metadata
+   *  loads - NaN there, normalized to 0 here so a caller can use it
+   *  directly as a divisor/percentage without its own NaN check). */
+  readonly duration: number;
   play(): void;
   pause(): void;
 }
@@ -27,6 +31,7 @@ export function localDriver(video: HTMLVideoElement): PlaybackDriver {
     get currentTime() { return video.currentTime; },
     set currentTime(seconds: number) { video.currentTime = seconds; },
     get paused() { return video.paused; },
+    get duration() { return video.duration || 0; },
     play() { video.play().catch(() => {}); },
     pause() { video.pause(); }
   };
@@ -147,6 +152,7 @@ export async function startCast(contentUrl: string, title: string, onRemoteState
     get currentTime() { return player.currentTime; },
     set currentTime(seconds: number) { player.currentTime = seconds; controller.seek(); },
     get paused() { return player.isPaused; },
+    get duration() { return player.duration || 0; },
     play() { if (player.isPaused) controller.playOrPause(); },
     pause() { if (!player.isPaused) controller.playOrPause(); }
   };
diff --git a/client/src/global.d.ts b/client/src/global.d.ts
index 71b37d8..505e5c7 100644
--- a/client/src/global.d.ts
+++ b/client/src/global.d.ts
@@ -101,6 +101,7 @@ interface CastContext {
 interface RemotePlayer {
   isPaused: boolean;
   currentTime: number;
+  duration: number;
 }
 
 interface RemotePlayerController {
diff --git a/client/src/views/player/Player.css b/client/src/views/player/Player.css
index 746edf1..9c705a4 100644
--- a/client/src/views/player/Player.css
+++ b/client/src/views/player/Player.css
@@ -164,9 +164,14 @@
 
 /* Replaces what used to be three separate floating pieces (a centered
    banner/notice column, a request toolbar cornered bottom-right, an
-   "Épisode suivant" link in the top bar) with one persistent bar - see
-   Player.html's own comment on why staying inside .playerWrap (not a
-   sibling positioned relative to it) also matters for plein écran. */
+   "Épisode suivant" link in the top bar) AND the browser's native
+   <video controls> with one persistent bar - see Player.html's own
+   comment on why staying inside .playerWrap (not a sibling positioned
+   relative to it) also matters for plein écran. Column layout (seek
+   bar row, then buttons row) so the two stack in normal flow instead of
+   two independently-guessed fixed offsets - same "stack, don't guess a
+   pixel offset" fix .topOverlay's own actionBar+presenceOverlay
+   grouping already needed (see its own comment). */
 .bottomBar {
   position: absolute;
   left: 10px;
@@ -174,19 +179,63 @@
   bottom: 10px;
   z-index: 6;
   display: flex;
-  align-items: center;
-  gap: 10px;
+  flex-direction: column;
+  gap: 8px;
   background: rgba(10, 8, 11, .8);
   border: 1px solid rgba(255, 255, 255, .08);
   border-radius: 12px;
-  padding: 8px 10px;
+  padding: 10px;
 }
 
+.bottomBarButtons { display: flex; align-items: center; gap: 10px; }
 .bottomBarZone { display: flex; align-items: center; gap: 8px; }
 .bottomBarZone.left { flex-shrink: 0; }
 .bottomBarZone.center { flex: 1; justify-content: center; min-width: 0; }
 .bottomBarZone.right { flex-shrink: 0; }
 
+/* Host: click/drag to seek (Player.ts). Follower: read-only, just a
+   position indicator - same "everyone sees the fill, only the host's
+   input actually does anything" split as the request buttons vs.
+   #ambientNotice above. The generous ::before hit-area (not just the
+   4px visual track) matters most for drag on a touch screen. */
+.progressBar {
+  position: relative;
+  height: 4px;
+  border-radius: 3px;
+  background: rgba(255, 255, 255, .18);
+  cursor: pointer;
+  touch-action: none; /* this app's own pointer handlers drive the drag, not the browser's default touch scroll/zoom gestures */
+}
+
+.progressBar.readOnly { cursor: default; }
+
+.progressBar::before {
+  content: '';
+  position: absolute;
+  top: -8px;
+  bottom: -8px;
+  left: 0;
+  right: 0;
+}
+
+.progressFill {
+  position: absolute;
+  top: 0;
+  bottom: 0;
+  left: 0;
+  width: 0%;
+  background: var(--accent);
+  border-radius: 3px;
+  pointer-events: none;
+}
+
+.timeLabel {
+  color: var(--muted);
+  font-size: 11.5px;
+  font-variant-numeric: tabular-nums;
+  white-space: nowrap;
+}
+
 /* Center zone: never more than one message at a time (see
    updateAmbientNotice in Player.ts) - "L'hôte contrôle la lecture" for
    a follower, or "Diffusion en cours sur le Chromecast" while casting
diff --git a/client/src/views/player/Player.html b/client/src/views/player/Player.html
index 585843d..4ec9a2d 100644
--- a/client/src/views/player/Player.html
+++ b/client/src/views/player/Player.html
@@ -1,5 +1,11 @@
 <div class="playerWrap">
-  <video id="video" playsinline></video>
+  <!-- disableremoteplayback: without it, Chrome adds its OWN native cast
+       icon to this element's native controls (see becomeHost in
+       Player.ts) the moment it detects a Cast-capable device on the
+       network - entirely separate from, and visually duplicating,
+       #castBtn's own custom integration (cast.ts). Standard attribute
+       for exactly this - see docs/architecture.md. -->
+  <video id="video" playsinline disableremoteplayback></video>
 
   <!-- Replaces the video content while casting - the local <video> is
        paused/torn down (see Player.ts's startCasting/cast.ts), so
@@ -60,48 +66,58 @@
   <!-- One bar, bottom-anchored, replacing what used to be three separate
        floating pieces (a centered banner/notice column, a request
        toolbar cornered bottom-right, an "Épisode suivant" link up in the
-       top bar) - see Player.css. The left zone shows exactly one of
-       #nextBtn/#requestToolbar - host or follower, never both, since
-       only the host ever has a queued item to advance and only a
-       follower ever has someone else's playback to request against.
-       Center is a single ambient status line (see updateAmbientNotice in
-       Player.ts - never more than one message at a time). Right is the
-       fullscreen toggle, for everyone. Staying INSIDE .playerWrap - not
-       a sibling positioned relative to it - is what keeps all of this
-       visible and clickable once plein écran targets the whole wrap
-       instead of just the <video> (see Player.ts's fullscreen handling
-       and docs/architecture.md). -->
+       top bar) AND the browser's own native <video controls> (see
+       becomeHost in Player.ts - never enabled any more, precisely
+       because that native bar used to render as its own always-on-top
+       layer fighting this one for the same space, especially visible
+       once plein écran started showing this bar too - see
+       docs/architecture.md). A seek bar on top, buttons below - staying
+       INSIDE .playerWrap, not a sibling positioned relative to it, is
+       what keeps all of this visible and clickable once plein écran
+       targets the whole wrap instead of just the <video>. -->
   <div id="bottomBar" class="bottomBar">
-    <div class="bottomBarZone left">
-      <button id="nextBtn" class="nextBtn hide">
-        <svg width="12" height="10" viewBox="0 0 14 10" aria-hidden="true">
-          <path d="M1 1 L6 5 L1 9 Z" fill="#fff"></path>
-          <path d="M7 1 L12 5 L7 9 Z" fill="#fff"></path>
-          <rect x="12.4" y="0.5" width="1.6" height="9" fill="#fff"></rect>
-        </svg>
-        Épisode suivant
-      </button>
-      <div id="requestToolbar" class="requestToolbar hide">
-        <button id="requestPauseBtn" class="requestBtn">
-          <svg width="9" height="9" viewBox="0 0 10 10" aria-hidden="true">
-            <rect x="1.5" y="1" width="2.4" height="8" fill="#fff"></rect>
-            <rect x="6.1" y="1" width="2.4" height="8" fill="#fff"></rect>
+    <!-- Host: click/drag to seek (see Player.ts's pointerdown/move/up
+         handlers). Follower: purely a read-only position indicator,
+         ticked from activeDriver just like the fill. -->
+    <div id="progressBar" class="progressBar">
+      <div id="progressFill" class="progressFill"></div>
+    </div>
+
+    <div class="bottomBarButtons">
+      <div class="bottomBarZone left">
+        <button id="playPauseBtn" class="iconBtn hide" title="Lecture / pause" aria-label="Lecture / pause"></button>
+        <button id="muteBtn" class="iconBtn" title="Muet" aria-label="Muet"></button>
+        <span id="timeLabel" class="timeLabel"></span>
+        <button id="nextBtn" class="nextBtn hide">
+          <svg width="12" height="10" viewBox="0 0 14 10" aria-hidden="true">
+            <path d="M1 1 L6 5 L1 9 Z" fill="#fff"></path>
+            <path d="M7 1 L12 5 L7 9 Z" fill="#fff"></path>
+            <rect x="12.4" y="0.5" width="1.6" height="9" fill="#fff"></rect>
           </svg>
-          Demander pause
-        </button>
-        <button id="requestResumeBtn" class="requestBtn">
-          <svg width="9" height="9" viewBox="0 0 10 10" aria-hidden="true">
-            <path d="M1.5 1 L8.5 5 L1.5 9 Z" fill="#fff"></path>
-          </svg>
-          Demander reprise
+          Épisode suivant
         </button>
+        <div id="requestToolbar" class="requestToolbar hide">
+          <button id="requestPauseBtn" class="requestBtn">
+            <svg width="9" height="9" viewBox="0 0 10 10" aria-hidden="true">
+              <rect x="1.5" y="1" width="2.4" height="8" fill="#fff"></rect>
+              <rect x="6.1" y="1" width="2.4" height="8" fill="#fff"></rect>
+            </svg>
+            Demander pause
+          </button>
+          <button id="requestResumeBtn" class="requestBtn">
+            <svg width="9" height="9" viewBox="0 0 10 10" aria-hidden="true">
+              <path d="M1.5 1 L8.5 5 L1.5 9 Z" fill="#fff"></path>
+            </svg>
+            Demander reprise
+          </button>
+        </div>
+      </div>
+      <div class="bottomBarZone center">
+        <span id="ambientNotice" class="ambientNotice hide"></span>
+      </div>
+      <div class="bottomBarZone right">
+        <button id="fullscreenBtn" class="fsBtn" title="Plein écran" aria-label="Plein écran"></button>
       </div>
-    </div>
-    <div class="bottomBarZone center">
-      <span id="ambientNotice" class="ambientNotice hide"></span>
-    </div>
-    <div class="bottomBarZone right">
-      <button id="fullscreenBtn" class="fsBtn" title="Plein écran" aria-label="Plein écran"></button>
     </div>
   </div>
 </div>
diff --git a/client/src/views/player/Player.ts b/client/src/views/player/Player.ts
index dc9300d..448ce15 100644
--- a/client/src/views/player/Player.ts
+++ b/client/src/views/player/Player.ts
@@ -6,7 +6,7 @@ import { getParty, leaveParty, connectParty, issueCastToken, revokeCastToken } f
 import type { PartyConnection } from '../../api/party';
 import { navigate } from '../../router';
 import type { CleanupFn, RouteParams } from '../../router';
-import { colorForName, escapeHtml, initialsFor } from '../../tiles';
+import { colorForName, escapeHtml, formatDuration, initialsFor } from '../../tiles';
 import { LOADING_HINT } from '../../loading';
 import type { BurnInChangedMsg, ItemChangedMsg, PartyPublicState, PauseRequestedMsg, PlaybackOptionsDto, ResumeRequestedMsg, SocketMember, StreamOptionsChangedMsg, TextSubtitleChangedMsg } from '../../types';
 import { joinMusicParty, leaveMusicParty } from '../../musicBar/MusicBar';
@@ -74,6 +74,36 @@ const EXIT_FULLSCREEN_SVG = `
     <path d="M9 4v5H4M15 4v5h5M9 20v-5H4M15 20v-5h5" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"></path>
   </svg>`;
 
+// #playPauseBtn's icon, swapped in place (updatePlayPauseBtn) - the
+// custom equivalent of the browser's own native <video controls> play/
+// pause button, which this app never enables any more (see becomeHost's
+// own comment for why: that native bar used to render as its own
+// always-on-top layer fighting this one for the same space).
+const PLAY_BTN_ICON_SVG = `
+  <svg viewBox="0 0 16 16" width="14" height="14" aria-hidden="true">
+    <path d="M3 2 L14 8 L3 14 Z" fill="#fff"></path>
+  </svg>`;
+const PAUSE_BTN_ICON_SVG = `
+  <svg viewBox="0 0 16 16" width="14" height="14" aria-hidden="true">
+    <rect x="3" y="2" width="3.5" height="12" fill="#fff"></rect>
+    <rect x="9.5" y="2" width="3.5" height="12" fill="#fff"></rect>
+  </svg>`;
+
+// #muteBtn's icon - local-only (video.muted directly, never synced -
+// see updateMuteBtn's own comment), so unlike every other bottom-bar
+// icon this one never reflects activeDriver/party state.
+const UNMUTED_ICON_SVG = `
+  <svg viewBox="0 0 16 16" width="14" height="14" aria-hidden="true">
+    <path d="M1 6h3l4-3.2v10.4l-4-3.2H1z" fill="#fff"></path>
+    <path d="M11 5.3a3 3 0 0 1 0 5.4" fill="none" stroke="#fff" stroke-width="1.3" stroke-linecap="round"></path>
+  </svg>`;
+const MUTED_ICON_SVG = `
+  <svg viewBox="0 0 16 16" width="14" height="14" aria-hidden="true">
+    <path d="M1 6h3l4-3.2v10.4l-4-3.2H1z" fill="#fff"></path>
+    <line x1="10.5" y1="5" x2="14.5" y2="9" stroke="#fff" stroke-width="1.3" stroke-linecap="round"></line>
+    <line x1="14.5" y1="5" x2="10.5" y2="9" stroke="#fff" stroke-width="1.3" stroke-linecap="round"></line>
+  </svg>`;
+
 /**
  * Route `/party/:id` - dispatches on the party's mediaType, fetched here
  * once. A video party still gets the full-page theater-mode takeover
@@ -166,6 +196,11 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
   const burnInHint = root.querySelector('#burnInHint')!;
   const castBtn = root.querySelector('#castBtn') as HTMLButtonElement;
   const fullscreenBtn = root.querySelector('#fullscreenBtn') as HTMLButtonElement;
+  const progressBar = root.querySelector('#progressBar') as HTMLElement;
+  const progressFill = root.querySelector('#progressFill') as HTMLElement;
+  const playPauseBtn = root.querySelector('#playPauseBtn') as HTMLButtonElement;
+  const muteBtn = root.querySelector('#muteBtn') as HTMLButtonElement;
+  const timeLabel = root.querySelector('#timeLabel')!;
 
   qualitySelect.innerHTML = QUALITY_PRESETS.map((q) => `<option value="${q.value}">${q.label}</option>`).join('');
 
@@ -238,6 +273,13 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
     castBtn.setAttribute('aria-pressed', 'false');
     castingScreen.classList.add('hide');
     activeDriver = localDriver(video);
+    // Local muting is meaningful again now that the local <video> is
+    // what's actually producing sound - see updateMuteBtn's own comment
+    // for why it's hidden while casting instead of controlling the
+    // (silent) local element for nothing.
+    muteBtn.classList.remove('hide');
+    updatePlayPauseBtn();
+    updateProgressBar();
     updateAmbientNotice();
     stopCast();
     revokeCastToken(partyId).catch(() => {});
@@ -292,7 +334,7 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
       const { token } = await issueCastToken(partyId);
       const streamPath = burnInSubtitleIndex ? burnInStreamUrl(partyId) : partyStreamUrl(partyId);
       const contentUrl = `${location.origin}${streamPath}?castToken=${encodeURIComponent(token)}`;
-      const driver = await startCast(contentUrl, itemTitleEl.textContent || 'Watch Party', sendLocalState);
+      const driver = await startCast(contentUrl, itemTitleEl.textContent || 'Watch Party', onDriverStateChanged);
 
       if (hls) { hls.destroy(); hls = null; }
       video.pause();
@@ -300,8 +342,11 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
       isCasting = true;
       castBtn.setAttribute('aria-pressed', 'true');
       castingScreen.classList.remove('hide');
+      // Nothing left for it to usefully control - the local <video> is
+      // paused/silent while the TV plays (see updateMuteBtn's own comment).
+      muteBtn.classList.add('hide');
       updateAmbientNotice();
-      sendLocalState();
+      onDriverStateChanged();
     } catch (err) {
       // The user cancelling the device picker rejects requestSession() the
       // same way a real failure does - neither is worth an alert() here,
@@ -331,6 +376,7 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
     }
     if (msg.isPaused && !activeDriver.paused) activeDriver.pause();
     if (!msg.isPaused && activeDriver.paused) activeDriver.play();
+    updateProgressBar(); // a follower's own read-only bar - see its own comment
     setTimeout(() => { suppressLocalEvents = false; }, 250);
   }
 
@@ -345,6 +391,102 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
     conn.sendPlaystate(activeDriver.paused, Math.round(activeDriver.currentTime * TICKS_PER_SECOND));
   }
 
+  /** #playPauseBtn's own icon - the custom equivalent of the native
+   *  <video controls> play/pause button (see becomeHost's comment for
+   *  why that's never enabled any more). Host-only (the button itself is
+   *  hidden for a follower), but harmless to call unconditionally - see
+   *  onDriverStateChanged below. */
+  function updatePlayPauseBtn() {
+    playPauseBtn.innerHTML = activeDriver.paused ? PLAY_BTN_ICON_SVG : PAUSE_BTN_ICON_SVG;
+  }
+
+  /** #muteBtn - deliberately reads/writes `video.muted` directly, never
+   *  activeDriver: muting is this device's own local presentation, not
+   *  party state - there is nothing to sync, and no meaning to it while
+   *  casting (the local <video> already produces no sound then - see
+   *  startCasting/stopCasting, which hide this button entirely instead). */
+  function updateMuteBtn() {
+    muteBtn.innerHTML = video.muted ? MUTED_ICON_SVG : UNMUTED_ICON_SVG;
+    muteBtn.setAttribute('aria-pressed', String(video.muted));
+  }
+
+  /** The seek bar's fill + time label - reads activeDriver, so it
+   *  already reflects whichever of local/cast is actually playing.
+   *  Called continuously (progressTicker, below) so it keeps moving
+   *  between discrete events, and once immediately after anything that
+   *  changes position/duration outside that ticker's own cadence
+   *  (seeking, a driver swap, a fresh applyRemoteState). */
+  function updateProgressBar() {
+    const duration = activeDriver.duration;
+    const current = activeDriver.currentTime;
+    progressFill.style.width = duration > 0 ? `${Math.min(100, (current / duration) * 100)}%` : '0%';
+    timeLabel.textContent = duration > 0 ? `${formatDuration(current)} / ${formatDuration(duration)}` : '';
+  }
+
+  /** Shared by every discrete play/pause/seek event this player reacts
+   *  to - the local <video>'s own native events (becomeHost) and a cast
+   *  session's RemotePlayerController events (startCasting's own
+   *  onRemoteStateChanged callback) alike - so the button icon, the
+   *  seek bar, and the party broadcast all stay in lockstep regardless
+   *  of which driver or which gesture actually caused the change. */
+  function onDriverStateChanged() {
+    updatePlayPauseBtn();
+    updateProgressBar();
+    sendLocalState();
+  }
+
+  let isDraggingProgress = false;
+
+  function seekFromPointerEvent(e: PointerEvent) {
+    const duration = activeDriver.duration;
+    if (!duration) return;
+    const rect = progressBar.getBoundingClientRect();
+    const fraction = Math.min(1, Math.max(0, (e.clientX - rect.left) / rect.width));
+    activeDriver.currentTime = fraction * duration;
+    onDriverStateChanged();
+  }
+
+  // Host-only (checked here, not just via the readOnly class - that one
+  // is purely a cursor/visual hint, see Player.css). Pointer events
+  // (not click/drag) so mouse and touch share one implementation, and
+  // setPointerCapture keeps the drag tracking even if the pointer leaves
+  // the bar's own bounds mid-gesture.
+  progressBar.addEventListener('pointerdown', (e) => {
+    if (!isHost) return;
+    isDraggingProgress = true;
+    progressBar.setPointerCapture(e.pointerId);
+    seekFromPointerEvent(e);
+  });
+  progressBar.addEventListener('pointermove', (e) => {
+    if (!isDraggingProgress) return;
+    seekFromPointerEvent(e);
+  });
+  progressBar.addEventListener('pointerup', () => { isDraggingProgress = false; });
+  progressBar.addEventListener('pointercancel', () => { isDraggingProgress = false; });
+
+  playPauseBtn.addEventListener('click', () => {
+    if (activeDriver.paused) activeDriver.play(); else activeDriver.pause();
+  });
+
+  muteBtn.addEventListener('click', () => {
+    video.muted = !video.muted;
+    updateMuteBtn();
+  });
+
+  // Ticks the seek bar/time label between discrete events - currentTime
+  // moves continuously while playing, with no event of its own for
+  // "still playing, time passed" the way play/pause/seeked have. Runs
+  // for everyone (host and follower alike - a follower's bar is
+  // read-only but still needs to visibly move), cheap no-op via the
+  // currentItemId guard whenever nothing's loaded at all.
+  let progressTicker: number | null = null;
+  progressTicker = window.setInterval(() => {
+    if (!currentItemId) return;
+    updateProgressBar();
+  }, 500);
+  updatePlayPauseBtn();
+  updateMuteBtn();
+
   /**
    * Promotes this client to host - called either at init (if we already
    * were) or on a live "hostChanged" event (the previous host left and the
@@ -359,17 +501,24 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
   function becomeHost(notify: boolean) {
     if (isHost) return;
     isHost = true;
-    video.controls = true;
+    // Native <video controls> deliberately never enabled - see
+    // Player.html's own comment on #bottomBar: that native bar used to
+    // render as its own always-on-top layer, invisible in fullscreen
+    // before that was fixed and directly overlapping/duplicating this
+    // one (its own cast icon, its own fullscreen toggle) once it was.
+    // playPauseBtn/progressBar below are the custom replacement.
     settingsWrap.classList.remove('hide');
     requestToolbar.classList.add('hide'); // the host acts directly - no requests to make once promoted mid-session
     nextBtn.classList.toggle('hide', !hasNextQueued);
+    playPauseBtn.classList.remove('hide');
+    progressBar.classList.remove('readOnly');
     updateAmbientNotice();
 
-    video.addEventListener('play', sendLocalState);
-    video.addEventListener('pause', sendLocalState);
-    video.addEventListener('seeked', sendLocalState);
+    video.addEventListener('play', onDriverStateChanged);
+    video.addEventListener('pause', onDriverStateChanged);
+    video.addEventListener('seeked', onDriverStateChanged);
     video.addEventListener('ended', () => { if (hasNextQueued) conn?.next(); });
-    if (!heartbeat) heartbeat = window.setInterval(sendLocalState, 3000);
+    if (!heartbeat) heartbeat = window.setInterval(onDriverStateChanged, 3000);
 
     // Burn-in (image) subtitle options are host-only (see
     // renderSubtitleOptions) - becoming host mid-session must unlock
@@ -515,6 +664,10 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
     currentItemId = itemId;
     clearError();
     loadingNotice.classList.remove('hide');
+    // Reset immediately rather than waiting for the next progressTicker
+    // tick (up to 500ms away) - the old item's leftover position/duration
+    // means nothing for whatever's loading now.
+    updateProgressBar();
 
     if (hls) {
       hls.destroy();
@@ -844,6 +997,7 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
     hasNextQueued = !!party.hasNext;
     updateAmbientNotice();
     requestToolbar.classList.toggle('hide', party.youAreHost);
+    progressBar.classList.toggle('readOnly', !party.youAreHost);
 
     // Before loadTrackOptions: renderSubtitleOptions' host-only gating
     // for burn-in options reads `isHost`, which becomeHost is what sets -
@@ -892,6 +1046,7 @@ function renderVideoPlayer(root: HTMLElement, partyId: string, party: PartyPubli
   // actual leak: previously, only the "Quitter" button ran any of this.
   return function cleanup() {
     if (heartbeat) clearInterval(heartbeat);
+    if (progressTicker) clearInterval(progressTicker);
     if (requestBannerTimer) clearTimeout(requestBannerTimer);
     if (hls) hls.destroy();
     document.removeEventListener('click', onDocumentClick);
diff --git a/docs/architecture.md b/docs/architecture.md
index ed6a4a4..74d4d86 100644
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -2659,6 +2659,81 @@ transition, neither of which this sandbox can exercise - worth trying
 for real once deployed, same as this project's other can't-verify-
 without-the-real-thing items.
 
+## The player's bottom bar was really two bars: replacing native `<video controls>`
+
+A direct follow-up to the player rework above, reported right after
+trying it for real: "two z-index layers, some elements duplicated,
+only in fullscreen." The actual cause was never a bug in the new
+bottom bar itself - it's that `video.controls = true` (set for the host
+since the very first version of this player) has always rendered the
+browser's own native control bar, a separate piece of UI that lives in
+its own always-on-top compositing layer, entirely independent of this
+app's DOM/CSS. That was never visually obvious before: fullscreen used
+to show *only* the video (the bug the previous section fixed), so the
+native bar was the only thing there was to look at. Once fullscreen
+correctly started showing this app's own overlays too, the native bar
+and the custom one both became visible at once - and specifically
+*duplicated*, not just crowded: Chrome adds its own cast icon to a
+`<video>`'s native controls automatically once it detects a Cast-
+capable device, entirely separate from `#castBtn`'s own integration
+(cast.ts) - "some elements duplicated, others not" was that icon
+sitting right next to this app's own, while native play/pause/seek/
+volume simply had no custom equivalent yet to *look* duplicated
+against.
+
+Two fixes, asked for as one:
+
+- **`disableremoteplayback`** on `<video>` - the standard attribute
+  for exactly this situation (a page with its own Cast integration
+  telling the browser not to add its own). Should have been there from
+  the start of "Casting to a Chromecast" above; this is where it was
+  actually noticed missing.
+- **Native `<video controls>` retired entirely**, replaced with a
+  custom transport bar - not just for fullscreen, everywhere, so there
+  is only ever one control surface instead of two that happen to
+  overlap less in the normal (windowed) case. `PlaybackDriver` (cast.ts)
+  gained `duration` alongside `currentTime`/`paused` - the one property
+  the existing abstraction didn't yet expose, needed for a seek bar to
+  compute a fraction or a target time regardless of which driver is
+  currently active.
+
+**What `#bottomBar` gained**: a seek bar (`#progressBar`/`#progressFill`)
+on its own row above the existing button row - column layout, so the
+two stack in normal flow rather than two independently-guessed fixed
+offsets (the same reasoning `.topOverlay`'s actionBar+presenceOverlay
+grouping already used). Host: pointer events (not click/drag, so mouse
+and touch share one implementation) seek by fraction of
+`activeDriver.duration`; a follower's bar is the same element, just
+read-only (`.readOnly` - a cursor/visual hint only, the actual pointerdown
+handler checks `isHost` itself regardless). A `progressTicker`
+(500ms) keeps the fill/time label moving between discrete events, since
+`currentTime` changes continuously while playing with no event of its
+own for that. `#playPauseBtn` (host-only, sharing the request buttons'
+left zone with `#nextBtn` - never more than one of the three visible at
+once) and `#muteBtn` (everyone, local-only - `video.muted` directly,
+never synced, since unlike play/pause this has no party-wide meaning at
+all - hidden while casting instead of controlling a local `<video>`
+that's already silent then) round out the replacement.
+
+One function, `onDriverStateChanged`, threads through every discrete
+event that used to just call `sendLocalState` directly - the local
+`<video>`'s own native play/pause/seeked events, and a cast session's
+`RemotePlayerController` events (`startCast`'s own `onRemoteStateChanged`
+callback) - so the button icon, the seek bar, and the party broadcast
+stay in lockstep regardless of which driver or which gesture caused
+the change, the same discipline every other party-wide state in this
+app already follows.
+
+Verified: full `typecheck`/`build` on the client. Checked in a real
+browser against the compiled bundle - injected the new bottom bar
+markup for both a "playing, unmuted" and a "paused, muted" state and
+confirmed the icons/fill/time label/readOnly cursor all render as
+designed. **Not verified**: an actual drag-to-seek gesture and real
+play/pause/volume behavior against a real `<video>` with a real source -
+this sandbox has no reachable Emby stream to attach one to, so the
+event wiring is confirmed by reading, not by dragging a real seek bar.
+Worth exercising for real once deployed.
+
 ## Known limitations
 
 - Playback always goes through `hls.js` against whatever Emby's