abacdai/wchem ? reverse-engineered prompt

Build me a standalone hand tracking web app that runs from a simple local server and opens in the browser with a webcam permission prompt. I want it to track my hand with the camera, show a small live camera preview, and let me use hand gestures to interact with a demo canvas.

Use pinch with thumb and index finger to draw or click and drag, and use a fist to erase or trigger a right click style action. The page should feel polished, with a nice glassy lab style interface, but keep the actual app logic separate so the hand tracking part can be reused in another project later.

Make sure there is a clear start camera button, a visible virtual cursor, and basic status feedback for tracking. I should be able to open the main HTML file through a local server and have it work right away. If you need current library details or browser docs, look them up online first.