html, body {
  width: 100%;
  height: 100%;
}
body {
  padding: 0;
  margin: 0;
  display: flex;
  justify-content: center;
  background: hsla(0, 0%, 5%);
}
canvas {
  max-width: 100%; 
  max-height: 100%;
  height: 100%;
  width: auto;
  object-fit: contain;
}