.btn-back {
    display: flex;
    position: fixed;
    width: 4.028571rem;
    height: 4.028571rem;
    border-radius: 50%;
    background-color: #FF8A62;
    text-align: center;
    color: #fff;
    font-size: 1.071429rem;
    font-weight: 700;
    right: 0.928571rem;
    bottom: 15.714286rem;
    justify-content: center;
    align-items: center;
    z-index: 999;
}