.button-triangle{position:relative}.button-triangle:after{content:"";opacity:1;border-top:12px solid #fff;border-left:12px solid #0000;border-right:12px solid #0000;width:0;height:0;transition:opacity .2s ease-in-out;position:absolute;bottom:-14px;left:60%;transform:translate(-50%)}.button-triangle:hover:after{opacity:1}