html,
body {
  margin: 0;
  padding: 0;
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  background: black;
  position: relative;
  touch-action: none;
}

canvas {
    margin: 0 auto;
    height: 100vh;
    width: 100vw;
    display: block;
}

#fps {
  position: absolute;
  bottom: 0;
  right: 0;
  color: white;
  display: none;
}

#loading {
  color: white;
  text-align: center;
  width: 100vw;
  min-height: 10em;
  margin: 0;
  position: absolute;               /* 2 */
  top: 50%;                         /* 3 */
  transform: translate(0, -50%
}