#go_top_button {
    display: none;
    position: fixed;
    background-color: transparent;
    border: 3px solid black;
    right: 15px;
    bottom: 10px;
    padding: 8px 15px;
    cursor: pointer;
    z-index: 999;
    font-size: 0;
}

#go_top_button:before {
    content: '\f176';
    font-family: FontAwesome;
    display: inline-block;
    font-size: 16px;
    font-style: normal;
    line-height: 1;
    font-weight: 700;
}

#go_top_button:hover {
    background: #000;
    border-color: #000;
    color: #fff;
}