.fade-in {
  animation: fadeIn 0.5s ease-in-out;
}
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.spinner {
  border: 4px solid rgba(0, 0, 0, 0.1);
  border-left-color: #4f46e5;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  animation: spin 1s linear infinite;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}