.loader {
  border: 16px solid #f3f3f3; /* Light grey */
  border-top: 16px solid #3498db; /* Blue */
  border-radius: 50%;
  width: 25px;
  height: 25px;
  animation: spin 0.5s linear infinite;
  
}
  
@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}