.whatsapp {
    width: 60px;
    height: 60px;
    margin: 0 auto;
    text-align: center;
    border-radius: 50%;
    right: 0;
    transition-duration: 0.5s;
    bottom: 0;
    position: fixed;
    right: 15px;
    bottom: 30px;
    z-index: 9999999;
}
.whatsapp .fa-whatsapp {
    padding-top: 10px;
    font-size: 40px;
    text-decoration: none;
    color: #008000;
}
.whatsapp:hover {
  background-color: #008000;
}
.whatsapp:hover .fa-whatsapp {
  color: #fff;
}