body:before {
  content: '';
  z-index: 10;
  position: fixed;
  opacity: 80%;
  top: 0;
  bottom: 0;
  right: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('https://uploads-ssl.webflow.com/61f56f86f784e70b89ea7637/61f583d545c6ae6e9513ec76_noise-transparent.png');
  animation: 0.3s infinite noise;
  pointer-events: none;
}
@keyframes noise {
  0%,
  100% {
    background-position: 0 0;
  }
  10% {
    background-position: -5% -10%;
  }
  20% {
    background-position: -15% 5%;
  }
  30% {
    background-position: 7% -25%;
  }
  40% {
    background-position: 20% 25%;
  }
  50% {
    background-position: -25% 10%;
  }
  60% {
    background-position: 15% 5%;
  }
  70% {
    background-position: 0% 15%;
  }
  80% {
    background-position: 25% 35%;
  }
  90% {
    background-position: -10% 10%;
  }
}