html body {
  font-size: 20pt;
  color: #111;
  font-family: sans-serif;
}

html,
body {
  background-color: black;
  height: 100%;
  margin: 0;
  display: flex;
  justify-content: center;
  align-items: center;
}

canvas {
  width: 100%;
  height: 100%;
  max-width: 100vw;
  max-height: 100vh;
  aspect-ratio: attr(width)/attr(height);
  object-fit: contain;
  image-rendering: pixelated;
}