.fa_hline {
    width: 80%;
    height: 1px;
    background: #ddd;
    margin: 30px auto 15px;
    max-width: 450px;
    position: relative;
}
.fa_hline span {
    height: 3px;
    top: -1px;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 50px;
    background: #086ab5;
    animation: fa_sumline_ani 5s linear infinite alternate;
}
@keyframes fa_sumline_ani{
0%{ width:20px;}
50%{ width:100px;}
100%{ width:20px;}
}

@-webkit-keyframes fa_sumline_ani /*Safari and Chrome*/
{
0%{ width:20px;}
50%{ width:100px;}
100%{ width:20px;}
}