fontawesome com radius border

HTML

    <div class="sosial-links">
    <a href="#"><i class="fa fa-facebook fa-lg"></i></a>
    <a href="#"><i class="fa fa-twitter fa-lg"></i></a>
    <a href="#"><i class="fa fa-google-plus fa-lg"></i></a>
    <a href="#"><i class="fa fa-pinterest fa-lg"></i></a>
</div>

CSS

.sosial-links a{
    display: block;
    float: left;
    width: 36px;
    height: 36px;
    border: 2px solid #909090;
    border-radius: 20px;
    margin-right: 7px; /*space between*/

} 
.sosial-links a i{
    padding: 12px 11px;
    font-size: 20px;
    color: #909090;
}