Edit in JSFiddle
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HTML
CSS
JavaScript
Resources
/*
*
* ==========================================
* FOR DEMO PURPOSE
* ==========================================
*
*/
body {
    background: #e8cbc0;
    background: -webkit-linear-gradient(to right, #e8cbc0, #636fa4);
    background: linear-gradient(to right, #e8cbc0, #636fa4);
    min-height: 100vh;
}

.social-link {
    width: 30px;
    height: 30px;
    border: 1px solid #ddd;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #666;
    border-radius: 50%;
    transition: all 0.3s;
    font-size: 0.9rem;
}

.social-link:hover, .social-link:focus {
    background: #ddd;
    text-decoration: none;
    color: #555;
}