footer.css

footer {
    color: white;
    position: absolute;
    bottom: 3rem;
    width: 100vw;
}

ul {
    margin:0;
    padding:0;
    display:flex;
    position: absolute;
    top: 50%;
    left:50%;
    transform: translate(-50%, -50%);
}

ul li {
    list-style:none;
    margin: 0 10px;
}

ul li a {
    position: relative;
    display: block;
    width: 60px;
    height: 60px;
    text-align: center;
    line-height: 60px;
    background: #171515;
    border-radius: 50%;
    font-size: 30px;
    color: #666;
    transition: .5s;

    display: grid;
    place-items: center;
}

ul li a:before {
    content: '';
    position: absolute;
    top:0;
    left:0;
    width:100%;
    height:100%;
    border-radius:50%;
    background: #d35400;
    transition: .5s;
    transform: scale(.9);
    z-index: -1;
}

ul li a:hover:before {
    transform: scale(1.2);
    box-shadow: 0 0 15px #d35400;
    filter: blur(3px);
}

ul li a:hover {
    color: #ffa502;
    box-shadow: 0 0 15px #d35400;
    text-shadow: 0 0 15px #d35400;
}