.wp-extras-back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    padding: 10px 20px;
    background-color: #0073aa;
    color: #fff;
    text-decoration: none;
    border-radius: 5px;
    display: none;
}

.wp-extras-back-to-top:hover {
    background-color: #005177;
}