#mainSlide {
    padding:10px 0;
    width: 70%;
    aspect-ratio: 800 / 368; /* 固定比率 */
    margin: 0 auto;          /* ← 中央寄せ（必要なら） */
}

#mainSlide .swiper-slide {
    width: 100%;
    height: 100%;
    overflow: hidden;
}

#mainSlide .swiper-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center var(--pos-y, 50%);
    display: block;
}
#mainSlide {
    width: 70%;
    aspect-ratio: 800 / 368;
    margin: 0 auto;
}

@media (max-width: 768px) {
    #mainSlide {
        width: 90%;
    }
    .swiper-button-next,
    .swiper-button-prev {
        transform: scale(0.4);
    }    
}