#back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    text-decoration: none;
    color: #ffffff;
    background-color: #7FB2D2;
    padding: 10px 20px;
    border-radius: 5px;
    display: none;
    z-index: 9999;
    transition: all .3s;
}

#back-to-top:hover {
    background-color: #689AB6;
}