body, html {
  margin: 0;
  padding: 0;
  height: 100%;
  background-color: black;
  overflow: hidden;
}

canvas {
  display: block;
}

#playground {
  color: white;
  position: absolute;
  left: 50%;
  top: 15%;
  transform: translate(-50%, -50%);
  font-size: 3vw;
  cursor: pointer; 
}