.whatsapp{
  position:fixed;
  bottom:25px;
  right:25px;
  background:#25D366;
  padding:15px;
  border-radius:50%;
  cursor:pointer;
  z-index:999;
  animation:float 2s infinite;
}

@keyframes float{
  0%{transform:translateY(0);}
  50%{transform:translateY(-5px);}
  100%{transform:translateY(0);}
}