.snow {
  opacity: 60%;
  position: absolute;
  top: 1500px;
  left: 0;
  z-index: 5;
  width: 100%;
  height: 100%;
  pointer-events: none;
  animation: snow-direction cubic-bezier(2, 0, 2, 1) 4s both alternate infinite;
}

@keyframes snow-direction {
  from {
    transform: translateX(-10%);
  }
  to {
    transform: translateX(10%);
  }
}

.snow:before,
.snow:after {
  content: '';
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  width: 10px;
  height: 10px;
  background-color: #fff;
  border-radius: 50%;
  filter: blur(1px);
  animation: snow 10s linear infinite;
  box-shadow:
    -5vw 10vh #fff,
    30vw 5vh #fff,
    55vw 5vh #fff,
    75vw 10vh #fff,
    105vw 15vh #fff,
    -10vw 30vh #fff,
    40vw 25vh #fff,
    60vw 20vh #fff,
    90vw 25vh #fff,
    20vw 40vh #fff,
    5vw 45vh #fff,
    65vw 45vh #fff,
    105vw 40vh #fff,
    50vw 50vh #fff,    
    30vw 50vh #fff,
    10vw 55vh #fff,
    20vw 60vh #fff,
    40vw 65vh #fff,
    60vw 60vh #fff,
    80vw 65vh #fff,
    5vw 70vh #fff,
    30vw 75vh #fff,
    55vw 85vh #fff,
    75vw 80vh #fff,
    105vw 75vh #fff,
    20vw 90vh #fff,
    -5vw 95vh #fff,
    65vw 95vh #fff,
    100vw 90vh #fff,
    
    -5vw 110vh #fff,
    30vw 105vh #fff,
    55vw 105vh #fff,
    75vw 110vh #fff,
    105vw 115vh #fff,
    -10vw 130vh #fff,
    40vw 125vh #fff,
    60vw 120vh #fff,
    90vw 125vh #fff,
    20vw 140vh #fff,
    5vw 145vh #fff,
    65vw 145vh #fff,
    105vw 140vh #fff,
    50vw 150vh #fff,    
    30vw 150vh #fff,
    10vw 155vh #fff,
    20vw 160vh #fff,
    40vw 165vh #fff,
    60vw 160vh #fff,
    80vw 165vh #fff,
    5vw 170vh #fff,
    30vw 175vh #fff,
    55vw 185vh #fff,
    75vw 180vh #fff,
    105vw 175vh #fff,
    20vw 190vh #fff,
    -5vw 195vh #fff,
    65vw 195vh #fff,
    100vw 190vh #fff;
}

.snow:after {
  position: absolute;
  left: 50px;
  top: 60px;
  animation-duration: 6s;
  width: 8px;
  height: 8px;
  opacity: 0.7;
  filter: blur(3px);
}

@keyframes snow {
  from {
    transform: rotate(10deg) translateY(-100vh);
  }
  to {
    transform: rotate(10deg) translateY(0);
  }
}