body {
   margin:0;
   padding:0;
   overflow:hidden;
   background-color: black;
}

#container canvas {
  width: 400px !important;
  height: 400px !important;
  position: absolute;
  top: 50%;
  left: 50%;
  margin-left: -200px;
  margin-top: -200px;
}

img {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 400px;
  height: 400px;
  margin-left: -200px;
  margin-top: -200px;
  mix-blend-mode: darken;
}