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HTML 

              
                <div class="wrapper">
            <div class="snow-wrapper">
                <div class="snow layer1 a"></div>
                <div class="snow layer1"></div> 
                <div class="snow layer2 a"></div>
                <div class="snow layer2"></div>
                <div class="snow layer3 a"></div>
                <div class="snow layer3"></div>
            </div>

            <div class="content-wrapper">
                <div class="content">
                    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur est sem, posuere a tellus non, efficitur dapibus mauris. Sed accumsan nisi ullamcorper lorem viverra sagittis ut eu sem. Vivamus felis elit, iaculis eu massa id, tincidunt luctus neque. Curabitur iaculis libero ante, sed pharetra neque ullamcorper in. Donec in justo eu ligula semper consequat sed a risus.</p> 
                    
                </div>
        </div>

    </div>
!

CSS 

              
                body {
       margin: 0;
    font-size: 22px;
    font-family: 'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
    color: #ffffff;
  filter: brightness(110%);
}
$s1:"";
$s2:"";
$s3:"";
@for $i from 1 through 300 {
    $s1: $s1 + random(1000)*0.1vw + " " + random(1000)*0.2vh + " " + 0 + " " + random(50)*-0.01rem + #fff;
    $s2: $s2 + random(1000)*0.1vw + " " + random(1000)*0.2vh + " " + 0 + " " + random(50)*-0.01rem + #fff;
    $s3: $s3 + random(1000)*0.1vw + " " + random(1000)*0.2vh + " " + 0 + " " + random(50)*-0.01rem + #fff;
    @if $i < 300 {
        $s1: $s1 + ",";
        $s2: $s2 + ",";
        $s3: $s3 + ",";
    }
}
.snow {
    border-radius: 50%;
    opacity: 0.8;
    position: absolute;
    top:-200vh;
    animation-name: fall;
    animation-timing-function: linear;
    animation-iteration-count: infinite;
}
.layer1 {
    width: 1.5rem;
    height: 1.5rem;
    filter:blur(2px);
    box-shadow: #{$s1};
    animation-duration: 48s;
}
.layer1.a {
    animation-delay: -24s;
}
.layer2 {
    width: 1.2rem;
    height: 1.2rem;
    filter:blur(3.5px);
    box-shadow: #{$s2};
    animation-duration: 64s;
}
.layer2.a {
    animation-delay: -32s;
}
.layer3 {
    width: 0.8rem;
    height: 0.8rem;
    filter:blur(6px);
    box-shadow: #{$s3};
    animation-duration: 80s;
}
.layer3.a {
    animation-delay: -40s;
}
@keyframes fall {
    100% {transform: translateY(400vh); }
}
.wrapper {
    height:100vh;
    perspective: 1px;
    transform-style: preserve-3d;
    overflow-x: hidden;
    overflow-y: auto;
}
.snow-wrapper {
    height: 200vh;
    background: radial-gradient(farthest-corner at 30vw 20vh,#7397a1 1%,#3f2c41 100%);
    transform-style: preserve-3d;
    z-index: -1;
}
.content-wrapper {
    opacity: 0.9;
    z-index: 1;
    background: #aaa;
    padding: 5vh 5vw;
    top:50vh;
    position: absolute;
    transform: translateZ(-1px) scale(2);
}
.content {
    margin: 0 auto;
    width: 50%;
}
!

JS 

              
                /* See step-by-step tutorial on how to create this at
https://youtu.be/8eyAoBBucHk


Want more? Visit for our CSS beginner tutorials!
https://redstapler.co
*/
!
999px

Console