#flake-container {
  position: fixed;
  pointer-events: none;
  overflow: hidden;
  left:0;top:0;
  width: 100%;
  height: 100%;
}

@-webkit-keyframes snow {
  from {top:-1%;}
  to {top:101%;}
}

@-moz-keyframes snow {
  from {top:-1%;}
  to {top:101%;}
}