.gallery-block--wrap{
    display: flex;
    /* mobile defaults use CSS variables set inline on the wrapper */
    margin-top: var(--gb-mt-mobile, 0);
    margin-bottom: var(--gb-mb-mobile, 0);
}
.gallery-block__grid{
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}
.gallery-block__item{
    display: flex;
    flex: 1 1 calc(25% - 1rem);
    aspect-ratio: 1 / 1;
    position: relative;
}
@media (max-width: 576px) {
    .gallery-block__item {
        flex: 1 1 calc(50% - 1rem);
    }
}
.gallery-block__item img{
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.gallery-block__item span{
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    display: flex;
    width: 110%;
    height: 110%;
    background-color: var(--wp--preset--color--blanc);
    transition: height 0.6s ease-in-out;
}
.gallery-block__item:nth-child(even) span{
    bottom: 0;
    top: unset;
}

@media (min-width: 768px) {
    .gallery-block--wrap {
        /* desktop defaults use CSS variables set inline on the wrapper */
        margin-top: var(--gb-mt-desktop, 0);
        margin-bottom: var(--gb-mb-desktop, 0);
    }
}