Template:Infobox ribbon row/styles.css

.tg-infobox-ribbon {
    position: absolute;
    right: 0;
    top: 0;
    display: block;
    filter: drop-shadow( 2px 3px 2px rgba( 0, 0, 0, 0.5 ) );
}

.tg-infobox-ribbon-content {
    background: var( --tg-color-progressive );
    clip-path: polygon( 0 0, 100% 0, 100% 100%, 50% calc( 100% - 8px ), 0 100% );
    width: 16px;
    min-height: 24px;
}