.galery-masonry{
    margin-bottom: 70px;
}
.galery-masonry .grid-item{
    width: 246px;
    margin-bottom: 16px;
}
.galery-masonry .grid-item--width2{
    width: 508px;
}
.galery-masonry .grid-item--width3{
    width: 246px;
}

@media (max-width: 508px) {
    .galery-masonry .grid-item--width2, .galery-masonry .grid-item--width3, .galery-masonry .grid-item {
        width: 100%;
    }
}