#to_top{
    display: none;
    position: fixed;
    color: #333;
    font-weight: bold;
    text-align: center;
    right: 40px;
    bottom: 50px;
    width: 50px;
    height: 50px;
    line-height: 50px;
    color: #222;
    background: #fff;
    border-radius: 50%;
    text-decoration: none;
    font-size: 16px;
    box-shadow: 0 0 5px rgb(0 0 0 / 45%);
}

@media (min-width: 320px) and (max-width: 1024px){
    #to_top{
        right: 10px;
        bottom: 15px;
        width: 40px;
        height: 40px;
        font-size: 12px;
        line-height: 40px;
    }
}