:root {
      --primary: #059669;
      --primary-hover: #047857;
      --primary-light: #ecfdf5;
      --primary-border: #a7f3d0;
      --accent: #10b981;
      --text-dark: #0f172a;
      --text-main: #334155;
      --text-muted: #64748b;
      --bg-main: #ffffff;
      --bg-alt: #f8fafc;
      --bg-card: #ffffff;
      --border-color: #e2e8f0;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
      --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -1px rgba(0,0,0,0.04);
      --shadow-lg: 0 10px 25px -5px rgba(5, 150, 105, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 16px;
      --container-width: 1200px;
      --transition: all 0.25s ease-in-out;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
      background-color: var(--bg-main);
      color: var(--text-main);
      line-height: 1.6;
    }

    body {
      overflow-x: hidden;
    }

    a {
      color: var(--primary);
      text-decoration: none;
      transition: var(--transition);
    }
    a:hover {
      color: var(--primary-hover);
    }

    /* Layout Containers */
    .container {
      width: 100%;
      max-width: var(--container-width);
      margin: 0 auto;
      padding: 0 20px;
    }

    section {
      padding: 70px 0;
      position: relative;
    }
    section:nth-child(even) {
      background-color: var(--bg-alt);
    }

    .section-header {
      text-align: center;
      max-width: 750px;
      margin: 0 auto 50px auto;
    }
    .section-tag {
      display: inline-block;
      padding: 4px 14px;
      background-color: var(--primary-light);
      color: var(--primary);
      font-weight: 600;
      font-size: 0.85rem;
      border-radius: 20px;
      margin-bottom: 12px;
      border: 1px solid var(--primary-border);
    }
    .section-title {
      font-size: 2rem;
      font-weight: 800;
      color: var(--text-dark);
      margin-bottom: 14px;
      line-height: 1.3;
    }
    .section-desc {
      font-size: 1rem;
      color: var(--text-muted);
    }

    /* Buttons */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 26px;
      font-size: 0.95rem;
      font-weight: 600;
      border-radius: var(--radius-md);
      cursor: pointer;
      border: 1px solid transparent;
      transition: var(--transition);
      white-space: nowrap;
    }
    .btn-primary {
      background-color: var(--primary);
      color: #ffffff !important;
      box-shadow: 0 4px 12px rgba(5, 150, 105, 0.25);
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      box-shadow: 0 6px 16px rgba(5, 150, 105, 0.35);
      transform: translateY(-2px);
    }
    .btn-outline {
      border-color: var(--primary);
      color: var(--primary);
      background-color: transparent;
    }
    .btn-outline:hover {
      background-color: var(--primary-light);
      transform: translateY(-2px);
    }

    /* Header & Navigation */
    .header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background-color: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo-container {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .ai-page-logo {
      height: 40px;
      width: auto;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 24px;
      list-style: none;
    }
    .nav-link {
      font-weight: 500;
      color: var(--text-dark);
      font-size: 0.95rem;
    }
    .nav-link:hover {
      color: var(--primary);
    }
    .header-actions {
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .nav-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      color: var(--text-dark);
      cursor: pointer;
    }

    /* Hero Section - STRICT NO IMAGES RULE ENFORCED */
    .hero-section {
      padding: 90px 0 70px 0;
      background: radial-gradient(circle at 10% 20%, rgba(236, 253, 245, 0.8) 0%, rgba(255, 255, 255, 1) 90%);
      border-bottom: 1px solid var(--border-color);
    }
    .hero-content {
      text-align: center;
      max-width: 900px;
      margin: 0 auto;
    }
    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: #ffffff;
      padding: 6px 18px;
      border-radius: 30px;
      font-size: 0.88rem;
      color: var(--primary);
      font-weight: 600;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--primary-border);
      margin-bottom: 24px;
    }
    .hero-title {
      font-size: 2.75rem;
      font-weight: 900;
      color: var(--text-dark);
      line-height: 1.25;
      letter-spacing: -0.5px;
      margin-bottom: 20px;
    }
    .hero-subtitle {
      font-size: 1.15rem;
      color: var(--text-main);
      margin-bottom: 36px;
      max-width: 780px;
      margin-left: auto;
      margin-right: auto;
    }
    .hero-actions {
      display: flex;
      justify-content: center;
      gap: 16px;
      margin-bottom: 50px;
      flex-wrap: wrap;
    }
    .hero-stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-top: 30px;
    }
    .hero-stat-card {
      background: #ffffff;
      padding: 22px 16px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-color);
      transition: var(--transition);
      text-align: center;
    }
    .hero-stat-card:hover {
      box-shadow: var(--shadow-md);
      border-color: var(--primary-border);
      transform: translateY(-3px);
    }
    .stat-number {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.2;
    }
    .stat-label {
      font-size: 0.85rem;
      color: var(--text-muted);
      margin-top: 4px;
    }

    /* Cards & Grids */
    .card-grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .card-grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }

    .feature-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 28px;
      transition: var(--transition);
      height: 100%;
      display: flex;
      flex-direction: column;
    }
    .feature-card:hover {
      box-shadow: var(--shadow-lg);
      border-color: var(--primary-border);
      transform: translateY(-4px);
    }
    .feature-icon-box {
      width: 48px;
      height: 48px;
      background: var(--primary-light);
      color: var(--primary);
      border-radius: var(--radius-sm);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1.25rem;
      margin-bottom: 20px;
    }
    .feature-card h3 {
      font-size: 1.2rem;
      color: var(--text-dark);
      margin-bottom: 10px;
    }
    .feature-card p {
      font-size: 0.92rem;
      color: var(--text-muted);
      flex-grow: 1;
    }

    /* Model Tag Cloud Section */
    .models-wrapper {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 30px;
      box-shadow: var(--shadow-sm);
    }
    .models-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
    }
    .model-tag {
      background: var(--bg-alt);
      border: 1px solid var(--border-color);
      padding: 8px 16px;
      border-radius: 20px;
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-dark);
      transition: var(--transition);
    }
    .model-tag:hover {
      background: var(--primary-light);
      border-color: var(--primary);
      color: var(--primary);
    }

    /* Comparison Section */
    .rating-banner {
      background: linear-gradient(135deg, #059669 0%, #047857 100%);
      color: #ffffff;
      border-radius: var(--radius-lg);
      padding: 32px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 40px;
      box-shadow: var(--shadow-md);
      flex-wrap: wrap;
      gap: 20px;
    }
    .rating-info h3 {
      font-size: 1.6rem;
      margin-bottom: 6px;
    }
    .rating-info p {
      opacity: 0.9;
      font-size: 0.95rem;
    }
    .rating-score-box {
      text-align: right;
    }
    .rating-stars {
      color: #fbbf24;
      font-size: 1.4rem;
      letter-spacing: 2px;
    }
    .rating-score {
      font-size: 2.2rem;
      font-weight: 900;
      line-height: 1;
      margin-top: 4px;
    }

    .table-container {
      overflow-x: auto;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      background: #ffffff;
    }
    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.92rem;
    }
    .compare-table th, .compare-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
    }
    .compare-table th {
      background-color: var(--bg-alt);
      color: var(--text-dark);
      font-weight: 700;
    }
    .compare-table tr:hover {
      background-color: rgba(236, 253, 245, 0.3);
    }
    .compare-highlight {
      font-weight: 700;
      color: var(--primary);
    }

    /* Case Studies (Non-Hero Images) */
    .case-card {
      background: #ffffff;
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-color);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    .case-img-wrap {
      width: 100%;
      height: 200px;
      overflow: hidden;
      background: #f1f5f9;
    }
    .ai-page-image {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }
    .case-content {
      padding: 20px;
    }
    .case-content h4 {
      font-size: 1.1rem;
      color: var(--text-dark);
      margin-bottom: 8px;
    }
    .case-content p {
      font-size: 0.88rem;
      color: var(--text-muted);
    }

    /* Timeline Process */
    .timeline-steps {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 16px;
      position: relative;
    }
    .timeline-step {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 20px 16px;
      text-align: center;
      position: relative;
    }
    .timeline-num {
      width: 36px;
      height: 36px;
      background: var(--primary-light);
      color: var(--primary);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      margin: 0 auto 12px auto;
    }
    .timeline-step h4 {
      font-size: 1rem;
      color: var(--text-dark);
      margin-bottom: 6px;
    }
    .timeline-step p {
      font-size: 0.82rem;
      color: var(--text-muted);
    }

    /* User Reviews */
    .review-card {
      background: #ffffff;
      border-radius: var(--radius-md);
      padding: 24px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .review-text {
      font-size: 0.92rem;
      color: var(--text-main);
      font-style: italic;
      margin-bottom: 16px;
    }
    .review-user {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid var(--border-color);
      padding-top: 12px;
    }
    .avatar-placeholder {
      width: 40px;
      height: 40px;
      background: var(--primary);
      color: #ffffff;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 0.9rem;
    }
    .user-info h5 {
      font-size: 0.95rem;
      color: var(--text-dark);
    }
    .user-info span {
      font-size: 0.8rem;
      color: var(--text-muted);
    }

    /* Accordion FAQ */
    .faq-container {
      max-width: 900px;
      margin: 0 auto;
    }
    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      width: 100%;
      padding: 18px 24px;
      text-align: left;
      background: none;
      border: none;
      font-size: 1rem;
      font-weight: 700;
      color: var(--text-dark);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      transition: var(--transition);
    }
    .faq-question:hover {
      background-color: var(--primary-light);
    }
    .faq-icon {
      font-size: 1.2rem;
      color: var(--primary);
      transition: var(--transition);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease-out;
      background: #ffffff;
    }
    .faq-answer-inner {
      padding: 0 24px 20px 24px;
      font-size: 0.92rem;
      color: var(--text-muted);
      line-height: 1.6;
    }
    .faq-item.active .faq-answer {
      max-height: 300px;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* Terminology Cloud */
    .glossary-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
    }
    .glossary-item {
      background: #ffffff;
      padding: 16px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--border-color);
    }
    .glossary-item h4 {
      color: var(--primary);
      font-size: 0.95rem;
      margin-bottom: 4px;
    }
    .glossary-item p {
      font-size: 0.82rem;
      color: var(--text-muted);
    }

    /* Form & Contact Section */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      gap: 40px;
      align-items: start;
    }
    .contact-info {
      background: #ffffff;
      padding: 32px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }
    .contact-item {
      display: flex;
      gap: 16px;
      margin-bottom: 24px;
    }
    .contact-icon {
      width: 42px;
      height: 42px;
      background: var(--primary-light);
      color: var(--primary);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      flex-shrink: 0;
    }
    .contact-text h4 {
      font-size: 0.95rem;
      color: var(--text-dark);
      margin-bottom: 2px;
    }
    .contact-text p {
      font-size: 0.9rem;
      color: var(--text-muted);
    }
    .qr-box {
      margin-top: 20px;
      padding-top: 20px;
      border-top: 1px solid var(--border-color);
      text-align: center;
    }
    .qr-box img {
      max-width: 160px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--border-color);
    }

    .form-box {
      background: #ffffff;
      padding: 36px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-md);
    }
    .form-group {
      margin-bottom: 20px;
    }
    .form-group label {
      display: block;
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-dark);
      margin-bottom: 6px;
    }
    .form-control {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 0.95rem;
      outline: none;
      transition: var(--transition);
    }
    .form-control:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(5, 150, 105, 0.15);
    }

    /* Footer Safety & Neutral Alignment */
    .footer {
      background-color: #0f172a;
      color: #cbd5e1;
      padding: 60px 0 30px 0;
      border-top: 1px solid #1e293b;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .footer-brand h3 {
      color: #ffffff;
      font-size: 1.3rem;
      margin-bottom: 12px;
    }
    .footer-brand p {
      font-size: 0.88rem;
      color: #94a3b8;
      max-width: 320px;
    }
    .footer-col h4 {
      color: #ffffff;
      font-size: 1rem;
      margin-bottom: 16px;
    }
    .footer-links {
      list-style: none;
    }
    .footer-links li {
      margin-bottom: 8px;
    }
    .footer-links a {
      color: #94a3b8;
      font-size: 0.88rem;
    }
    .footer-links a:hover {
      color: var(--accent);
    }
    .friend-links-area {
      padding-top: 24px;
      border-top: 1px solid #1e293b;
      margin-bottom: 24px;
    }
    .friend-links-area h5 {
      color: #94a3b8;
      font-size: 0.85rem;
      margin-bottom: 10px;
    }
    .friend-links-flex {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
    }
    .friend-links-flex a {
      color: #94a3b8;
      font-size: 0.85rem;
    }
    .friend-links-flex a:hover {
      color: #ffffff;
    }
    .footer-bottom {
      text-align: center;
      padding-top: 20px;
      border-top: 1px solid #1e293b;
      font-size: 0.82rem;
      color: #64748b;
    }

    /* Floating Widget */
    .float-kefu {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      background: var(--primary);
      color: #ffffff !important;
      padding: 12px 18px;
      border-radius: 30px;
      box-shadow: var(--shadow-lg);
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 600;
      font-size: 0.9rem;
    }
    .float-kefu:hover {
      background: var(--primary-hover);
      transform: scale(1.05);
    }

    /* Responsive Adjustments */
    @media (max-width: 992px) {
      .hero-title { font-size: 2.2rem; }
      .card-grid-3, .card-grid-4, .glossary-grid { grid-template-columns: repeat(2, 1fr); }
      .timeline-steps { grid-template-columns: repeat(3, 1fr); gap: 12px; }
      .contact-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .hero-stats-grid { grid-template-columns: repeat(2, 1fr); }
    }

    @media (max-width: 768px) {
      .nav-menu {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-menu.active { display: flex; }
      .nav-toggle { display: block; }
      .hero-title { font-size: 1.8rem; }
      .card-grid-3, .card-grid-4, .glossary-grid, .timeline-steps { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
    }