Video Play Icon over image

Place an icon centered on an image, using screen reader text for accessibility. (Bootstrap)

HTML

<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap.min.css">
<div class="container">
    <div class="row">
        <div class="video-overlay col-sm-4 col-xs-6"> <a href="#">
    <img src="http://placehold.it/600x450/face8d" />
    <div class="icon"><div class="sr-only">Play</div></div>
    </a> 
        </div>
    </div>
</div>

CSS

img {
    max-width: 100%;
    height: auto;
}
.video-overlay .icon {
    position: absolute;
    background-image: url('http://placehold.it/100x100/f00');
    margin: 0 auto;
    background-size: contain;
    width: 20%;
    height: 100px;
    bottom: 35%;
    left: 40%;
    background-repeat: no-repeat;
    background-position: bottom;
}
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    padding: 0;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}
.sr-only-focusable:active, .sr-only-focusable:focus {
    position: static;
    width: auto;
    height: auto;
    margin: 0;
    overflow: visible;
    clip: auto;
}