.snowflakes {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    pointer-events: none;
}

.snowflake {
    position: absolute;
    background-color: #fff;
    opacity: 0.8;
    border-radius: 50%;
    animation: fall linear infinite;
}

@keyframes fall {
    0% {
        transform: translateY(0);
    }
    100% {
        transform: translateY(calc(100vh + 100px));
    }
}