Snow

snow.css

##need-to-change-urls–in-css
##Example
##background-image: ##url('https://s3-eu-west-1.amazonaws.com/static-ressources/s1.png'), ##url('https://s3-eu-west-1.amazonaws.com/static-ressources/s2.png'), ##url('https://s3-eu-west-1.amazonaws.com/static-ressources/s3.png');
  ##z-index:100;

<div class="snow" />
<style>
.editor-stage .snow {
  height:50px;
  background: #fff;
}
.snow{
  position:fixed;
  pointer-events:none;
  top:0;
  left:0;
  right:0;
  bottom:0;
  height:100vh;
  background: none;
  background-image: url('https://s3-eu-west-1.amazonaws.com/static-ressources/s1.png'), url('https://s3-eu-west-1.amazonaws.com/static-ressources/s2.png'), url('https://s3-eu-west-1.amazonaws.com/static-ressources/s3.png');
  z-index:100;
  -webkit-animation: snow 10s linear infinite;
  -moz-animation: snow 10s linear infinite;
  -ms-animation: snow 10s linear infinite;
  animation: snow 10s linear infinite;
}
@keyframes snow {
  0% {background-position: 0px 0px, 0px 0px, 0px 0px;}
  50% {background-position: 500px 500px, 100px 200px, -100px 150px;}
  100% {background-position: 500px 1000px, 200px 400px, -100px 300px;}
}
@-moz-keyframes snow {
  0% {background-position: 0px 0px, 0px 0px, 0px 0px;}
  50% {background-position: 500px 500px, 100px 200px, -100px 150px;}
  100% {background-position: 400px 1000px, 200px 400px, 100px 300px;}
}
@-webkit-keyframes snow {
  0% {background-position: 0px 0px, 0px 0px, 0px 0px;}
  50% {background-position: 500px 500px, 100px 200px, -100px 150px;}
  100% {background-position: 500px 1000px, 200px 400px, -100px 300px;}
}
@-ms-keyframes snow {
  0% {background-position: 0px 0px, 0px 0px, 0px 0px;}
  50% {background-position: 500px 500px, 100px 200px, -100px 150px;}
  100% {background-position: 500px 1000px, 200px 400px, -100px 300px;}
}
</style>