html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: #000;
  touch-action: none;
  -webkit-user-select: none;
  user-select: none;
}

canvas {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  display: block;
}

canvas[hidden] { display: none; }

body.idle { cursor: none; }