.back-to-top {
    cursor: pointer;
    position: fixed;
    bottom: 70px;
    right: 50px;
    z-index: 22;
    display: none;
    height: 50px;
    width: 50px;
    border: solid 1px #afadad;
    border-radius: 10px;
    text-align: center;
}

    .back-to-top > span {
        font-weight: bold;
        font-size: 20px;
        color: #afadad;
        position: relative;
        top: 8px;
    }