/* Reset some defaults */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  :root {
    --primary-color: #007bff;
    --primary-dark: #0056b3;
    --success-color: #28a745;
    --success-dark: #218838;
    --info-color: #17a2b8;
    --info-dark: #117a8b;
    --neutral-bg: #f0f4f8;
    --accent-bg: #f0f8ff;
    --card-bg: #ffffff;
    --text-color: #333;
    --heading-color: #2c3e50;
    --shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    --font-main: 'Poppins', 'Segoe UI', Arial, sans-serif;
  }
  
  /* Base Styles */
  body {
    font-family: var(--font-main);
    background: linear-gradient(135deg, var(--neutral-bg), #d9e2ec);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    padding: 20px;
    display: flex;
    flex-direction: column;
  }
  
  /* Headings */
  h1, h2 {
    text-align: center;
    margin-bottom: 24px;
    font-weight: 700;
    color: var(--heading-color);
    letter-spacing: 0.5px;
  }
  
  /* Containers */
  #questionContainer, #result, #quizResults, #certificateModal {
    background: var(--card-bg);
    border-radius: 16px;
    box-shadow: var(--shadow);
    padding: 30px;
    max-width: 920px;
    margin: 24px auto;
    transition: all 0.3s ease-in-out;
  }
  
  /* Utility */
  .hidden {
    display: none;
  }
  
  /* Question Block */
  .question-block {
    background-color: var(--accent-bg);
    border-left: 5px solid var(--primary-color);
    padding: 18px;
    border-radius: 10px;
    margin-bottom: 24px;
  }
  
  /* Labels */
  label {
    display: block;
    margin: 10px 0;
    font-weight: 500;
    font-size: 1rem;
    cursor: pointer;
  }
  
  /* Buttons */
  button {
    background: var(--primary-color);
    color: #fff;
    padding: 12px 28px;
    margin: 10px;
    font-size: 16px;
    font-weight: 600;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.3s ease, transform 0.2s ease, box-shadow 0.2s ease;
  }
  
  button:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  }
  
  /* Special Buttons */
  #certificateActions button {
    background-color: var(--success-color);
  }
  
  #certificateActions button:hover {
    background-color: var(--success-dark);
  }
  
  #quizResults button {
    background-color: var(--info-color);
  }
  
  #quizResults button:hover {
    background-color: var(--info-dark);
  }
  
  /* Review Blocks */
  .question-review {
    background-color: #f9f9f9;
    border-left: 5px solid #6c757d;
    padding: 16px;
    border-radius: 10px;
    margin-bottom: 20px;
  }
  
  /* Inputs */
  input[type="text"] {
    width: 100%;
    padding: 14px;
    margin-top: 12px;
    border-radius: 8px;
    border: 1px solid #ccc;
    font-size: 16px;
    transition: border-color 0.3s, box-shadow 0.3s;
  }
  
  input[type="text"]:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 6px rgba(0, 123, 255, 0.4);
    outline: none;
  }
  
  /* Certificate Modal */
  #certificateModal h2 {
    margin-bottom: 12px;
    font-size: 30px;
    color: var(--primary-color);
  }
  
  #certificateModal p {
    margin: 12px 0;
    font-size: 18px;
  }
  
  /* Progress Indicator */
  #progress {
    margin-top: 14px;
    text-align: center;
    font-weight: 600;
    font-size: 1.1rem;
  }
  
  /* Navigation Bar */
  nav {
    background-color: #fff;
    font-family: var(--font-main);
    padding: 12px 0;
    width: 100%;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.06);
  }
  
  nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    text-align: center;
  }
  
  nav ul li {
    display: inline-block;
    margin: 0 18px;
  }
  
  nav ul li a {
    text-decoration: none;
    color: var(--primary-color);
    font-size: 1.15em;
    padding: 10px 16px;
    border-radius: 6px;
    transition: background-color 0.3s ease, color 0.3s ease;
  }
  
  nav ul li a:hover {
    background-color: var(--primary-dark);
    color: #fff;
  }
  
  nav ul li a:active {
    background-color: #5f4bbf;
    color: #fff;
  }
  
  /* Responsive Design */
  @media (max-width: 768px) {
    body {
      padding: 12px;
    }
  
    #questionContainer, #result, #quizResults, #certificateModal {
      padding: 20px;
      margin: 14px;
    }
  
    button {
      width: 100%;
      margin: 10px 0;
    }
  
    input[type="text"] {
      width: 100%;
    }
  
    nav ul {
      display: block;
    }
  
    nav ul li {
      display: block;
      margin: 10px 0;
    }
  
    nav ul li a {
      display: block;
      padding: 14px;
    }
  }
  
  @media (max-width: 480px) {
    h1, h2 {
      font-size: 22px;
    }
  
    #certificateModal h2 {
      font-size: 20px;
    }
  
    button {
      font-size: 14px;
      padding: 10px 20px;
    }
  }
  
  .certificate-preview-section {
    margin-top: 30px;
  }
  
  .certificate-preview-section h2 {
    margin-bottom: 15px;
    font-size: 1.5rem;
  }
  
  .certificate-preview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 15px;
  }
  
  .certificate-preview-grid .cert-thumb {
    width: 100%;
    height: auto;
    max-height: 200px;
    object-fit: cover;
    border: 2px solid #ccc;
    border-radius: 8px;
    cursor: pointer;
    transition: transform 0.3s ease;
  }
  .certificate-preview-grid .cert-thumb:hover {
    transform: scale(1.05);
  }
  
  /* Scoped modal styles */
  #certificateModal.modal-preview {
    display: none;
    position: fixed;
    z-index: 9999;
    padding-top: 60px;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.8);
  }
  
  #certificateModal.modal-preview .modal-content-preview {
    display: block;
    margin: auto;
    max-width: 80%;
    max-height: 80%;
    border-radius: 12px;
  }
  
  #certificateModal.modal-preview .close-preview {
    position: absolute;
    top: 30px;
    right: 40px;
    color: #fff;
    font-size: 40px;
    font-weight: bold;
    cursor: pointer;
    transition: 0.3s;
  }
  
  #certificateModal.modal-preview .close-preview:hover {
    color: #ffcc00;
  }

  .exam-info-modal.modal {
    display: none;
    position: fixed;
    z-index: 999;
    left: 0; top: 0;
    width: 100%; height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.6);
  }
  
  .exam-info-modal .modal-content {
    background-color: #fff;
    margin: 8% auto;
    padding: 20px 30px;
    border-radius: 10px;
    width: 90%;
    max-width: 700px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  }
  
  .exam-info-modal .close {
    float: right;
    font-size: 28px;
    font-weight: bold;
    color: #888;
    cursor: pointer;
  }
  
  .exam-info-modal .close:hover {
    color: #000;
  }
  
  .exam-info-modal .career-impact-box {
    margin-top: 20px;
    padding: 15px 20px;
    background-color: #f0f6ff;
    border-left: 6px solid #2a8dd2;
    border-radius: 8px;
  }
  
  .exam-info-modal .career-impact-box h3 {
    margin-top: 0;
    color: #2a8dd2;
  }
  
  .exam-info-modal .career-impact-box ul {
    padding-left: 20px;
    margin: 5px 0 10px 0;
  }
  
  .exam-info-modal .career-impact-box li {
    margin-bottom: 5px;
  }