#back-to-top {

    display: none;

    position: fixed;

    bottom: 30px;

    right: 30px;

    z-index: 9999;

    background: #384766;

    color: #fff;

    padding: 8px 18px;

    border-radius: 10%;

    text-align: center;

    font-size: 24px;

    cursor: pointer;

    transition: background 0.3s ease;

}

#back-to-top:hover {

    background: #555;

}