nav header{padding-left:.2rem!important;padding-right:.2rem!important;max-width:100%!important}.box{position:relative}h1:before{content:"";height:2px;background:#0400ff;display:inline-block;position:absolute;bottom:-6px;width:0;transform:translate(-50%,-50%);transition:all .9s;margin-left:50%}h1:hover:before{width:100%}