If you're looking to recreate a similar effect using CSS alone, check out this CSS fiddle I've put together.
hr.fancy-line {
border: 0;
height: 1px;
background-image: -webkit-linear-gradient(left, rgba(0,0,0,0), rgba(215,215,215,0.75), rgba(0,0,0,0));
background-image: -moz-linear-gradient(left, rgba(0,0,0,0), rgba(215,215,215,0.75), rgba(0,0,0,0));
background-image: -ms-linear-gradient(left, rgba(0,0,0,0), rgba(215,215,215,0.75), rgba(0,0,0,0));
background-image: -o-linear-gradient(left, rgba(0,0,0,0), rgba(215,215,215,0.75), rgba(0,0,0,0));
box-shadow: 0px -2px 4px rgba(136,136,136,0.75);
}
<hr class="fancy-line"></hr>
Challenged by adding the gradient to the shadow? Any thoughts on how this could be enhanced?