.img {
  position: absolute;
  height: 100000px;
  width: 100000px;
  top: -8500px;
  left: -8000px;
  animation-timing-function: cubic-bezier(0.250, 0.250, 0.750, 0.750);
  animation-name: float;
  animation-iteration-count: infinite;
}

#scene { height:0; list-style:none; }

#img-2 {
  opacity: 0;
  background: url('https://silverfish.nl/wp-content/themes/silvertheme-child/img/dust.jpg');
  background-repeat: repeat;
  animation-duration: 450s;
}

#img-3 {
  opacity: 0.25;
  background: url('https://silverfish.nl/wp-content/themes/silvertheme-child/img/bubbles-water.png');
  background-repeat: repeat;
  background-position:left;
  animation-duration: 150s;
}
/*ANIMATIONS*/

@keyframes twinkle {
  0% {
    transform: translate(0px, 0px);
  }
  30% {
    opacity: 0;
  }
  50% {
    opacity: 0.75;
  }
  70% {
    opacity: 0;
  }
  100% {
    transform: translate(175px, 100px);
  }
}

@keyframes float {
  0% {
    transform: translate(0px, 0px);
  }
  100% {
      transform:translate(0px, -2000px);
  }
}