body {
  margin: 0;
  padding: 0;
  background-color: #222;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
}

canvas {
  display: block;
  margin: 0 auto;
  max-width: 100%;
  height: auto;
  aspect-ratio: 800 / 300;
  border: 2px solid #333;
  touch-action: none;
}