body {
  font-family: 'Segoe UI', sans-serif;
  background: #f9fafb;
  color: #333;
  padding: 1rem;
  margin: 0;
}

.back-button {
  display: inline-block;
  margin: 1rem;
  padding: 0.5rem 1rem;
  background: #333;
  color: #fff;
  text-decoration: none;
  border-radius: 5px;
}

.challenge-header {
  padding: 0 2rem;
  margin-bottom: 2rem;
}

.challenge-header h1 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.challenge-header p {
  font-size: 1rem;
  color: #555;
}

.loader-container {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 60vh;
}

.loader {
  width: 60px;
  height: 60px;
  border: 8px solid #eee;
  border-top-color: #333;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

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

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .loader {
    animation: none;
  }
}