[agent-pushpinderbal]

Fix tablet layouts that can remain at portrait width after rotating or leaving native video fullscreen, and keep sidebar navigation clear of the logo in short landscape windows. Reapply mobile viewport constraints after fullscreen exit without reloading the page or restarting playback, and let the sidebar reserve space for its brand and account controls.

Play now reveals and focuses the committed player while the stream is loading. Stop and browser Back restore the selected title, browsing scroll position, focus, search query, and category without briefly unmounting Search.

Validation:

• Frontend TypeScript/Vite build passed.
• 22 relevant Chromium browser workflows passed, covering desktop/mobile playback, navigation, Search, and rotation.
• Six relevant WebKit workflows passed, including desktop/mobile reveal and return, playback controls, and simulated iPad fullscreen/rotation recovery.
• Inspected desktop/mobile screenshots. Native iPad fullscreen recovery is simulated in the browser tests; confirmation on the affected iPad remains useful.