body {
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f4f6f8;
    color: #333;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    flex-direction: column;
    text-align: center;
  }
  
  .card {
    background-color: #fff;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.05);
    max-width: 500px;
  }
  
  h1 {
    font-size: 2rem;
    margin-bottom: 10px;
    color: #2c3e50;
  }
  
  p {
    font-size: 1rem;
    color: #555;
    margin-bottom: 30px;
  }
  
  .spinner {
    border: 6px solid #f3f3f3;
    border-top: 6px solid #3498db;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 0 auto;
  }
  
  @keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
  }
  
  @media (max-width: 600px) {
    .card {
      padding: 20px;
    }
    h1 {
      font-size: 1.5rem;
    }
  }