body {
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  background-color: #111;
}

canvas {
  image-rendering: pixelated;
  width: 100%;
  height: 100%;
  max-width: 100vmin;
  max-height: 100vmin;
}

canvas.fullscreen {
  max-width: 100vw;
  max-height: 100vh;
}

#saving {
  position: absolute;
  top: 10px;
  left: 10px;
  width: 10px;
  height: 10px;
  background-color: #fff;
}