CSS lineheight çalışmama sorunu

<div class="footer-icons">
                    <a href="#"><i class="fa fa-facebook"></i></a>
                    <a href="#"><i class="fa fa-twitter"></i></a>
                    <a href="#"><i class="fa fa-linkedin"></i></a>
                    <a href="#"><i class="fa fa-github"></i></a>
            </div>

.footer-icons {
    margin-top: 25px;
}
.footer-icons a {
    background-color: #33383b;
    border-radius: 2px;
    color: #ffffff;
    cursor: pointer;
    display: inline-block;
    font-size: 20px;
    height: 35px;
    line-height: 35px;
    margin-bottom: 5px;
    margin-right: 3px;
    text-align: center;
    width: 35px;
}
.footer-icons :hover {
    background: #3b5998 none repeat scroll 0 0;
}