.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 10001; /* above .auth-screen (10000) */
  animation: fadeIn 0.2s ease;
}

.loading-overlay.active {
  display: flex;
}

.spinner {
  width: 50px;
  height: 50px;
  border: 4px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: var(--radius-full);
  animation: spin 0.8s linear infinite;
  box-shadow: var(--shadow-lg);
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}