#stars {
    width: 1px;
    height: 1px;
    background: transparent;
    box-shadow: 100px 200px #FFF, 300px 400px #FFF, 500px 600px #FFF; /* Ejemplo de sombras de caja */
    animation: animStar 50s linear infinite;
}

#stars::after {
    content: " ";
    position: absolute;
    top: 2000px;
    width: 1px;
    height: 1px;
    background: transparent;
    box-shadow: 100px 200px #FFF, 300px 400px #FFF, 500px 600px #FFF; /* Repetir las mismas sombras */
}

#stars2 {
    width: 2px;
    height: 2px;
    background: transparent;
    box-shadow: 150px 250px #FFF, 350px 450px #FFF, 550px 650px #FFF; /* Ajustar para diferentes tamaños */
    animation: animStar 100s linear infinite;
}

#stars2::after {
    content: " ";
    position: absolute;
    top: 2000px;
    width: 2px;
    height: 2px;
    background: transparent;
    box-shadow: 150px 250px #FFF, 350px 450px #FFF, 550px 650px #FFF;
}

#stars3 {
    width: 3px;
    height: 3px;
    background: transparent;
    box-shadow: 200px 300px #FFF, 400px 500px #FFF, 600px 700px #FFF;
    animation: animStar 150s linear infinite;
}

#stars3::after {
    content: " ";
    position: absolute;
    top: 2000px;
    width: 3px;
    height: 3px;
    background: transparent;
    box-shadow: 200px 300px #FFF, 400px 500px #FFF, 600px 700px #FFF;
}



@keyframes animStar {
    from {
        transform: translateY(0px);
    }
    to {
        transform: translateY(-2000px);
    }
}