.snowflake {
    position: absolute;
    background-image: var(--snowflake-url);
    background-size: cover;
    border-radius: 50px;
    animation: fall 2s linear infinite;
}

@keyframes fall {
    0% {
        transform: translate(50%, 50%);
        opacity: 1;
    }

    100% {
        transform: translate(50%, 1000%);
        opacity: 0;
    }
}