body {
  background-color: grey;
    margin : 0;
	justify-content : center;
	align-items : center;

  /* leave it to hide the scrollbars */
  overflow: hidden;
}
canvas {
  display: block;
    padding: 0;
    margin: auto;
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
	--w: min(100vh, 100vw);
    height: var(--w) !important;
    width: var(--w) !important;"  
  
}