JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css">
<ul>
    <li class="exp"><a class="fa fa-camera-retro fa-3x"></a></li>
</ul

CSS

.exp{
    width:80px;
    height:80px;
    border-radius:50%;
    box-shadow: 0 0 0 1px #000 inset;
    line-height: 80px;
    text-align: center;
    display: inline-block;
}

.exp:hover {
    background-color: #000;
}

.fa-camera-retro {
    color: #000;
    width: inherit;
    height: inherit;
    line-height: inherit;
}

.fa-camera-retro:hover {
    color: #fff;
}