.whatsapp {
  position:fixed;
  width:60px;
  height:60px;
  bottom:40px;
  left:15px;
  background-color: green;
  color:#FFF;
  border-radius:50px;
  text-align:center;
  font-size:30px;
  z-index:100;
}

.whatsapp-icon {
  margin-top:15px;
}