html {
  margin: 0;
  padding: 0;
}
body{
  position: absolute;
  top: 50%;
  left: 40%;
  transform: translate(-50%, -50%) scale(1.5);
  background-color: grey;
  display: flex;
  justify-content: center;
  align-items: center;
}

canvas {
  display: block;
}