.loader{position:relative;width:120px;height:20px;border-bottom:2px solid #f3f3f3;overflow:hidden}.loader:before{content:"";position:absolute;bottom:0;left:0;width:100%;height:2px;background-color:#3498db;animation:spin 2s linear infinite}@keyframes spin{0%{transform:translateX(0)}to{transform:translateX(-100%)}}