body{
text-align:center;
font-family: sans-serif;
margin: 0;
}

.modal {
    width: 100%;
    height: 100vh;
    background: rgba(0,0,0,0.8);
    position: absolute;
    top: 0;
    left: 0;
    display: flex;

    animation: modal 2s;
    visibility: hidden;
    opacity: 0;

}
.contenido {
    margin: auto;
    width: 40%;
    height: 40%;
   background: white;
   border-radius: 10px;

}

#cerrar {
    display: none;
}
#cerrar + label {
    position: absolute;
    color: #fff;
    font-size: 25px;
    z-index: 50;
    background: darkred;
    height: 40px;
    width: 40px;
    line-height: 40px;
    border-radius: 50%;
    right: 10px;
    cursor: pointer;

    animation: modal 2s;



    
    visibility: hidden;
    opacity: 0;


}

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

    }
}