ul li a{position:relative;display:inline-block;color:inherit;text-decoration:none;padding-bottom:2px;transition:color .3s ease-in-out}ul li a:after{content:"";position:absolute;width:0;height:2px;background:#fff;bottom:0;left:0;transition:width .3s ease-in-out}ul li a:hover:after{width:100%}ul li a:hover{color:#f1f1f1}