html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  overflow: hidden;
  background: #000 url('../../balance-of-fear.jpg') center center / cover no-repeat fixed;
}

#canvas {
  position: absolute;
  top: 0;
  left: 0;
  display: block;
  width: 100vw;
  height: 100vh;
}