.fc_gallery {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 0;
}

.fc_gallery a {
    aspect-ratio: 1 / 1;
}

@media (max-width: 640px) {
    .fc_gallery {
        display: flex;
        flex-wrap: wrap;
    }

    .fc_gallery a {
        flex-basis: 33.3%;
    }

    .fc_gallery a:nth-child(5n + 4) ,
    .fc_gallery a:nth-child(5n + 5) {
        flex-basis: 50%;
    }
}