@keyframes move-forever {
  0% {
    transform: translate3d(-90px,0,0);
  }
  100% {
    transform: translate3d(85px,0,0);
  }
}

.parallax > use {
  animation: move-forever 25s cubic-bezier(.55,.5,.45,.5) infinite;
}

.parallax > use:nth-child(1) {
  animation-delay: -2s;
  animation-duration: 14s;
}

.parallax > use:nth-child(2) {
  animation-delay: -3s;
  animation-duration: 20s;
}

.parallax > use:nth-child(3) {
  animation-delay: -4s;
  animation-duration: 26s;
}

.parallax > use:nth-child(4) {
  animation-delay: -5s;
  animation-duration: 40s;
}