.body {
  /* set margin to 0 and overflow to hidden, to go fullscreen */
  /* margin-top: 20px; */
  /* overflow: hidden; */
}

.button{
  font-size:3vw;
  color: rgba(250,250,250,0.7);
}

#on_off{
  position: absolute;
  font-size:7vw;
  top:  0px;
  left: 0px;
  background-color: rgba(200,200,200,0.3);
}

#canvas{
  position: absolute;
  top: 0px;
  left: 0px;
  z-index: -1;
}