.galeria {
    width: 90%;
    margin: auto;
    list-style: none;
    padding: 10px;
    box-sizing: border-box;
    display: flex;
    flex-wrap: wrap;
}
.galeria img {
    width: 150px;
    height: 100px;
}
.modal {
    visibility: hidden;
    opacity: 0;
}
.modal:target {
    visibility: visible;
    opacity: 1;
    transition: all 0.5s;
    position: fixed;
    background: rgba(0,0,0,0.8);
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.modal h3 {
    font-size: 20px;
    color: darkorange;
}
.imagen {
    width: 100%;
    height: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
}
.imagen a {
    color: #fff;
    font-size: 40px;
    text-decoration: none;
    margin: 0 10px;
}
.imagen a:nth-child(2) {
    margin: 0;
    height: 100%;
    flex-shrink: 2;
}
.imagen img {
    width: 600px;
    height: 100%;
    max-width: 100%;
    border: 7px solid #fff;
    box-sizing: border-box;
}
.cerrar {
    display: block;
    background: darkorange;
    width: 25px;
    height: 25px;
    margin: 15px auto;
    text-align: center;
    text-decoration: none;
    font-size: 25px;
    color: #000;
    padding: 5px;
    border-radius: 50%;
    line-height: 100%;
}