.fa-whatsapp{
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}
#whatsapp .wtsapp{
  position: fixed;
  transform: all .5s ease;
  background-color: #25d366;
  display: block;
  text-align: center;
  box-shadow: 0 0 20px rgba(0,0,0,0,0.15);
  border-radius: 50px;
  border-right: none;
  color: #fff;
  font-weight: 700;
  font-size: 30px;
  bottom: 70px;
  left: 20px;
  border: 0;
  z-index: 9999;
  width: 50px;
  height: 50px;
  line-height: 50px;
}
#whatsapp .wtsapp:before{
  content: "";
  position: absolute;
  z-index: -1;
  left: 50%;
  top: 50%;
  transform: translateX(-50%) translateY(-50%);
  display: block;
  width: 60px;
  height: 60px;
  background-color: #25d366;
  border-radius: 50%;
  -webkit-animation:pulse-border 1500ms ease-out infinite;
  animation:pulse-border 1500ms ease-out infinite; 
} 
#whatsapp .wtsapp:focus{
  border: none;
  outline: none;
}
@keyframes pulse-border{
  0%{transform: translateX(-50%) translateY(-50%) translateZ(0) scale(1); opacity: 1;}
  100%{transform: translateX(-50%) translateY(-50%) translateZ(0) scale(1.5); opacity: 0;}
}