.wp-widget-rakuten-banner ul.wp-widget-rakuten-banner-wrapper {
    display: flex;
    list-style: none;
    padding: 0;
    margin: 0;
    flex-wrap: wrap;
    justify-content: left;
    max-width: 1200px;
}
.wp-widget-rakuten-banner ul.wp-widget-rakuten-banner-wrapper > li {
    width: 50%;
    padding: 4px;
    box-sizing: border-box;
}
.wp-widget-rakuten-banner ul.wp-widget-rakuten-banner-wrapper > li > a {
    display: block;
    text-align: center;
}
.wp-widget-rakuten-banner ul.wp-widget-rakuten-banner-wrapper > li > a > img {
    max-width: 100%;
    max-height: 65px;
}
@media only screen and (max-width: 420px) {
    .wp-widget-rakuten-banner ul.wp-widget-rakuten-banner-wrapper > li {
        width: 290px;
    }
}