img {
    max-width: 100%;
}
.photo-list {
    padding: 150px 0;
    width: 90%;
    max-width: 1000px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
}
.photo-list li {
    width: 49%;
    margin-right: 2%;
    margin-bottom: 2%;
}
@media screen and (max-width: 768px) {
    .photo-list li:nth-child(2n) {
        margin-right: 0;
    }
}
@media screen and (min-width: 769px) {
    .photo-list li {
        width: 32%;
        margin-right: 2%;
        margin-bottom: 2%;
    }
    .photo-list li:nth-child(3n) {
        margin-right: 0;
    }
}
/* アニメーション設定 */
.scr-target {
    opacity: 0;
    transform: translate3d(0, 50px, 0);
}
.scr-target.is-active {
    opacity: 1;
    transform: translate3d(0, 0, 0);
    transition: 2s;
}