html, body {
  margin: 0;
  padding: 0;
}

main {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  background-color: #000000;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 0px;
}

canvas {
  
    object-fit: contain;
    max-height: 100%;
    max-width: 100%;
 
}