body {
    font-family: Arial, sans-serif;
    padding: 2rem;
    background-color: #f9f9f9;
  }
  
  h1 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
  }
  
  #card-container {
    max-width: 400px;
    margin: 0 auto;
  }