._bgi-mv {
    background-image: url(../image/top/bgi-mv.png);
}

@media only screen and (min-width: 768px) {
    ._bgi-mv {
        background-image: url(../image/top/bgi-mv-pc.png);
    }
}

._anchor-topics:hover ._anchor-topics-bgi {
    width: 130%;
    height: 130%;
}

.swiper-slide {
    width: calc((100% - (3 * 30px)) / 3.5);
}