body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  background: #222;
  overflow: hidden;
}
video {
  display: none;
}
#outputCanvas {
  width: 100vw;
  height: 100vh;
  object-fit: cover;
  position: absolute;
  top: 0;
  left: 0;
}
#threeCanvas {
  width: 100vw;
  height: 100vh;
  position: absolute;
  top: 0;
  left: 0;
}

#game-cubes {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
}

#game-cubes .cube {
  display: inline-block;
  width: 48vw;
  height: 48vh;
  margin: 2px;
  background: rgba(255,255,255,0.2);
}