html {
  height: 100%;
  width: 100%;
  background-color: #000000;
}

#canvas {
  position: absolute;
  width: 90vw;
  height: 45vw;
  z-index: 1;
  border: 1px solid #ffffff;
  left: calc(50% - 45vw);
}

img {
  visibility: hidden;
}