.gallery__list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(3, 1fr);
    grid-gap: 20px;
}

@media screen and (max-width: 480px) {
    .gallery__list {
        grid-template-columns: repeat(2, 1fr);
        grid-template-rows: repeat(2, 200px 123px);
    }
}

.gallery__item {
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-pack: center;
    -ms-flex-pack: center;
    justify-content: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
    width: 100%;
}

.gallery__item:first-child {
    grid-row-start: 1;
    grid-column-start: 1;
    grid-row-end: 3;
    grid-column-end: 3;
}

@media screen and (max-width: 480px) {
    .gallery__item {
        grid-row-start: auto !important;
        grid-row-end: auto !important;
    }
    .gallery__item:nth-child(3n + 1) {
        grid-column-start: 1;
        grid-column-end: 3;
    }
}

.gallery__item img {
    display: block;
    -o-object-fit: cover;
    object-fit: cover;
    max-width: 650px;
    max-height: 100%;
    width: 100%;
    height: 100%;
}