body {
    margin: 0;
}

.loader {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  background: black;
  color: white;
  text-align: center;
  display: flex;
}

.loader:before {
  content: 'LOADING...';
  margin: auto;
}

canvas {
    display: block;
    position: absolute;
}