.modal {
    width: 100%;
    height: 100vh;
    background: rgba(0,0,0,0.8);
    
    position: absolute;
    top: 0;
    left: 0;
    
    display: flex;
    
    animation: modal 2s 3s forwards;
    visibility: hidden;
    opacity: 0;
}

.contenido {
    margin: auto;
    width: 40%;
    height: 90%;
    
    
}

#cerrar {
    display: none;
}

#cerrar + label {
    position: absolute;
    color: rgb(247, 215, 38);
    font-size: 25px;
    z-index: 50;
    background: rgb(241, 165, 51);
    height: 40px;
    width: 40px;
    line-height: 40px;
    border-radius: 50%;
    right: 150px;
    top: 10px;
    cursor: pointer;
    
    animation: modal 3s 4s forwards;
    visibility: hidden;
    opacity: 0;
}

#cerrar:checked + label, #cerrar:checked ~ .modal {
    display: none;
}

@keyframes modal {
    100% {
        visibility: visible;
        opacity: 1;
    }
}