.fade-in {  
  opacity: 0;  
  animation: fadeIn 1s ease-in forwards;  
}  
  
@keyframes fadeIn {  
  to { opacity: 1; }  
}  
a, button, .dropbtn {  
  transition: background 0.3s, color 0.3s, box-shadow 0.3s;  
}  
  
a:hover, button:hover, .dropbtn:hover {  
  background: #4353fa;  
  color: #fff;  
  box-shadow: 0 2px 8px #b1bafc;  
  cursor: pointer;  
}