I want to build a lightweight web-based player, “Gaust”, that revolves around playlists rather than single-video viewing. The single most important feature is letting people bring in an existing YouTube playlist and start watching immediately. Playlist import must work in two ways: • OAuth sign-in so a user can pull any of their own playlists through the YouTube Data API • Manual mode where the same result is achieved by pasting a playlist URL or ID, no login required Once a list is inside the app, users should see the usual thumbnail-and-title view, choose where to start, jump or skip ahead, and keep videos playing continuously via the YouTube iFrame API. Standard controls—play/pause, next/previous, seek bar, shuffle and repeat—need to feel as smooth as the native YouTube experience. I’m happy with React, Vue, or a clean vanilla-JS approach as long as the final build is responsive and easy to host on a standard web server. Please document your code, include a short README that covers setup (API key, OAuth credentials, local build), and keep personal data handling to session memory only. Acceptance is based on: • Both import methods functioning reliably • Clear, responsive UI that works on mobile and desktop • Continuous playback without breaking YouTube’s terms of service • Delivered source, build instructions, and brief usage guide