body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    min-height: 100vh;
    z-index: -1;
    background: url(../Imagenes/FondoHorizontal02.jpg) no-repeat center center;
    background-size: cover;
    background-repeat: no-repeat;
    pointer-events: none;
}

@media only screen and (min-width: 380px) and (max-width: 768px) {
    body::before {
        background: url(../Imagenes/FondoVertical02.jpg) no-repeat center center;
        background-size: cover;
        background-repeat: no-repeat;
    }
}