/* Font */
body {
    font-family: 'Prompt', sans-serif;
    margin: 0;
    padding: 0;
    background: #f0f2f5;
  }
  
  /* Layout */
  .container {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    padding: 1rem;
    box-sizing: border-box;
  }
  
  /* Card */
  .card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 400px;
    text-align: center;
  }
  
  /* Text */
  h1 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
  }
  
  input[type="text"] {
    width: 100%;
    padding: 0.8rem;
    margin-bottom: 1rem;
    border-radius: 8px;
    border: 1px solid #ccc;
    font-size: 1rem;
    box-sizing: border-box;
  }
  
  button {
    width: 100%;
    padding: 0.8rem;
    background-color: #007bff;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
  }
  
  button:hover {
    background-color: #0056b3;
  }
  
  .error {
    color: red;
    margin-top: 1rem;
    font-size: 0.9rem;
  }
  
  /* PDF Viewer */
  .pdf-viewer {
    width: 100%;
    max-width: 800px;
    text-align: center;
  }
  
  .pdf-viewer iframe {
    width: 100%;
    height: 80vh;
    border: 1px solid #ccc;
    border-radius: 12px;
  }
  
  .back-btn {
    margin-top: 20px;
    padding: 10px 20px;
    font-size: 1rem;
    background-color: #444;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
  }
  
  .back-btn:hover {
    background-color: #222;
  }
  
  /* Responsive adjustments */
  @media (max-width: 480px) {
    .card {
      padding: 1.2rem;
    }
  
    h1 {
      font-size: 1.2rem;
    }
  
    input[type="text"],
    button {
      font-size: 0.95rem;
      padding: 0.6rem;
    }
  
    .back-btn {
      font-size: 0.95rem;
      padding: 0.6rem 1.2rem;
    }
  }
  /* Text */
h1 {
    font-size: clamp(1.2rem, 5vw, 1.8rem);  /* ปรับขนาดอัตโนมัติตามหน้าจอ */
    margin-bottom: 1.5rem;
    line-height: 1.4;
    word-break: break-word;
    white-space: normal;
    font-weight: bold;
  }
  @media (max-width: 360px) {
    .card {
      padding: 1rem;
    }
  
    h1 {
      font-size: 1.1rem;
    }
  
    input[type="text"],
    button {
      font-size: 0.9rem;
      padding: 0.5rem;
    }
  }