#app-fallback {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  font-family: system-ui, sans-serif;
  color: #333;
  text-align: center;
  padding: 24px;
}
#app-fallback.error { color: #c62828; }
#app-fallback .spinner {
  width: 36px; height: 36px;
  border: 4px solid #e0e0e0;
  border-top-color: #1a237e;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin-bottom: 16px;
}
@keyframes spin { to { transform: rotate(360deg); } }
#app-fallback button {
  margin-top: 16px; padding: 10px 24px;
  background: #1a237e; color: #fff;
  border: none; border-radius: 6px;
  cursor: pointer; font-size: 14px;
}