/* === Fog Animation === */
.fog-layer {
  position: fixed;
  top: 0;
  left: 0;
  width: 200%;
  height: 100%;
  background: url('https://www.transparenttextures.com/patterns/fog.png') repeat;
  opacity: 0.2;
  animation: driftFog 120s linear infinite;
  z-index: 2;
}

@keyframes driftFog {
  0% {
    transform: translateX(0);
  }
  100% {
    transform: translateX(-50%);
  }
}