th.active{color:#fff}th.active .arrow{opacity:1}.arrow{display:inline-block;vertical-align:middle;width:0;height:0;margin-left:5px;opacity:.66}.arrow.asc{border-left:4px solid transparent;border-right:4px solid transparent;border-bottom:4px solid #fff}.arrow.dsc{border-left:4px solid transparent;border-right:4px solid transparent;border-top:4px solid #fff}