body {
  margin:0;
padding:0;
display:block;
width:100vw;
height:100vh;
overflow:hidden;
  background-color: black;
  object-fit: contain;
}
canvas {
max-width: 100%;
max-height: 100%;
bottom: 0;
left: 0;
margin: auto;
overflow: auto;
position: fixed;
right: 0;
top: 0;
object-fit: contain;
}