.highlight-pen{position:relative;z-index:1;display:inline-block}.highlight-pen::before{content:'';position:absolute;left:0;bottom:0.1em;width:100%;height:1em;background:#8BC63F;z-index:-1;animation:swipeHighlight 1.2s ease-out forwards;transform:scaleX(0);transform-origin:left}@keyframes swipeHighlight{to{transform:scaleX(1)}}