.snowflake{
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: white;
    position: absolute;
    top: -8px;
    animation: fall 10s linear;
}

@keyframes fall {
    form{ }  
    to{
        transform: translateY(100vh);
        opacity: 0;
    }
}