body {
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #000;
}

main {
  width: 100vmin;
  height: 100vmin;
  display: flex;
  align-items: center;
  justify-content: center;
}

canvas {
  width: 100vmin !important;
  height: 100vmin !important;
}