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<div class="snow"></div>
html {
height: 100%;
background: linear-gradient(#321 30%, #667);
overflow: hidden;
}
.snow, .snow:before, .snow:after {
position: absolute;
top: -400px;
left: 0;
bottom: 0;
right: 0;
background-image: radial-gradient(4px 4px at 379px 102px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 212px 309px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 311px 147px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 131px 234px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 335px 63px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 184px 253px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 371px 33px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(6px 6px at 181px 280px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 380px 91px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 390px 359px, rgba(255, 255, 255, 1) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 57px 259px, rgba(255, 255, 255, 0.8) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 184px 128px, rgba(255, 255, 255, 0.8) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 348px 158px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 362px 285px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 242px 22px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(6px 6px at 257px 163px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(6px 6px at 21px 66px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 11px 298px, rgba(255, 255, 255, 1) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 24px 69px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 299px 53px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(6px 6px at 256px 54px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 347px 275px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(6px 6px at 283px 193px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 97px 193px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 91px 53px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 309px 286px, rgba(255, 255, 255, 1) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 273px 213px, rgba(255, 255, 255, 1) 50%, rgba(0, 0, 0, 0)), radial-gradient(4px 4px at 306px 262px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 30px 199px, rgba(255, 255, 255, 1) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 50px 6px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(6px 6px at 140px 259px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 63px 352px, rgba(255, 255, 255, 0.6) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 93px 189px, rgba(255, 255, 255, 0.8) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 22px 317px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 30px 186px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 121px 225px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 247px 66px, rgba(255, 255, 255, 0.8) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 111px 52px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0)), radial-gradient(5px 5px at 381px 10px, rgba(255, 255, 255, 0.7) 50%, rgba(0, 0, 0, 0)), radial-gradient(3px 3px at 339px 342px, rgba(255, 255, 255, 0.9) 50%, rgba(0, 0, 0, 0));
background-size: 400px 400px;
animation: snow 5s linear infinite;
content: "";
}
.snow:after {
margin-left: -133.3333333333px;
opacity: 0.4;
animation-duration: 10s;
animation-direction: reverse;
filter: blur(3px);
}
.snow:before {
animation-duration: 15s;
animation-direction: reverse;
margin-left: -200px;
opacity: 0.65;
filter: blur(1.5px);
}
@keyframes snow {
to {
transform: translateY(400px);
}
}
Also see: Tab Triggers