.banner-box {
    display: flex;
    justify-content: space-between;
}
.banner-box li {
    width: 48%;
    list-style: none;
}
.banner-box li:hover {
    opacity: 0.8;
}
.banner-box li img {
    width: 100%;
}
@media not all and (min-width: 768px) {
    .banner-box {
        display: block;
    }
    .banner-box li {
        width: 100%;
    }
    .banner-box li:first-child {
        margin-bottom: 20px;
    }
}

/*ひとつだけ表示したい*/

.banner-area{
    text-align: center;
}
.banner-area a:hover {
    opacity: 0.8;
}
@media not all and (min-width: 768px) {

    .banner-area img {
        width: 100%;
    }
}

/*ひとつだけ表示したい*/