#btnWhatsApp 
{
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 100;
    /* background-color: #ffffff; */
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    width: 100px;
}

#btnWhatsApp:hover 
{
    background-color: #485c4f;
}