.social a {
    display: inline-block;
    width: 36px;
    height: 36px;
    margin: 0 5px;
    opacity: .9;
    transition: opacity .3s;
}

.social a img {
    width: 20px;
    height: 20px;
    padding: 10px;
}

.social a:hover {
    opacity: .5;
}