body {
  margin: 0;
}

canvas {
  display: block;
  width: min(100vw, calc(100dvh * 16 / 9));
  height: auto;
  margin: 0 auto;
}

#clearVideo {
  display: none;
  position: fixed;
  width: 80%;
  max-width: 900px;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}