<!DOCTYPE html>
<html>
<head>
<style>
body { margin: 0; background: #000; }
iframe { width: 100vw; height: 100vh; border: none; }
</style>
</head>
<body>
<iframe src="https://www.youtube.com/embed/dQw4w9WgXcQ?autoplay=1&mute=0" allow="autoplay; fullscreen"></iframe>
</body>
</html>