:root {
      --primary: #1e40af;
      --primary-light: #3b82f6;
      --primary-bright: #2563eb;
      --accent: #0284c7;
      --accent-warm: #f59e0b;
      --bg-main: #f8fafc;
      --bg-card: #ffffff;
      --text-dark: #0f172a;
      --text-muted: #475569;
      --border-color: #e2e8f0;
      --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
      --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
      --shadow-lg: 0 10px 15px -3px rgba(30, 64, 175, 0.1), 0 4px 6px -2px rgba(30, 64, 175, 0.05);
      --radius: 12px;
      --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }

    * {
      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-dark);
      line-height: 1.6;
    }

    body {
      overflow-x: hidden;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
    }

    .container {
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* Header & Navigation */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .brand-logo {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
      color: var(--primary);
      font-weight: 700;
      font-size: 1.25rem;
    }

    .brand-logo img.ai-page-logo {
      height: 38px;
      width: auto;
      object-fit: contain;
      display: block;
    }

    .nav-links {
      display: flex;
      align-items: center;
      list-style: none;
      gap: 0;
    }

    .nav-links li a {
      text-decoration: none;
      color: var(--text-muted);
      font-weight: 500;
      font-size: 0.95rem;
      padding: 8px 14px;
      border-radius: 6px;
      transition: var(--transition);
      display: inline-block;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--primary-bright);
      background-color: #eff6ff;
    }

    .nav-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 22px;
      font-size: 0.95rem;
      font-weight: 600;
      border-radius: 8px;
      text-decoration: none;
      cursor: pointer;
      transition: var(--transition);
      border: 1px solid transparent;
      line-height: 1.2;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary-bright), var(--primary));
      color: #ffffff;
      box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, var(--primary), #1d4ed8);
      box-shadow: 0 6px 14px rgba(37, 99, 235, 0.4);
      transform: translateY(-2px);
    }

    .btn-outline {
      border-color: var(--primary-bright);
      color: var(--primary-bright);
      background: #ffffff;
    }

    .btn-outline:hover {
      background: #eff6ff;
      border-color: var(--primary);
      color: var(--primary);
    }

    .btn-accent {
      background: #f59e0b;
      color: #ffffff;
    }

    .btn-accent:hover {
      background: #d97706;
      transform: translateY(-2px);
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      color: var(--text-dark);
      cursor: pointer;
    }

    /* Sections */
    section {
      padding: 70px 0;
      position: relative;
    }

    .section-header {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 48px;
    }

    .section-tag {
      display: inline-block;
      padding: 4px 12px;
      font-size: 0.85rem;
      font-weight: 600;
      color: var(--primary-bright);
      background: #dbeafe;
      border-radius: 9999px;
      margin-bottom: 12px;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: var(--text-dark);
      line-height: 1.3;
      margin-bottom: 12px;
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
    }

    /* Hero Section (Strictly pure CSS, NO IMAGES) */
    .hero-section {
      padding: 90px 0 80px;
      background: radial-gradient(circle at 80% 20%, #dbeafe 0%, transparent 40%),
                  radial-gradient(circle at 20% 80%, #e0e7ff 0%, transparent 40%),
                  #ffffff;
      border-bottom: 1px solid var(--border-color);
      position: relative;
      overflow: hidden;
    }

    .hero-wrapper {
      display: grid;
      grid-template-columns: 1.2fr 0.8fr;
      gap: 40px;
      align-items: center;
    }

    .hero-content h1 {
      font-size: 2.6rem;
      line-height: 1.25;
      font-weight: 800;
      color: #0f172a;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-content h1 span {
      color: var(--primary-bright);
      background: linear-gradient(135deg, #1e40af, #2563eb, #0284c7);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-lead {
      font-size: 1.15rem;
      color: var(--text-muted);
      margin-bottom: 32px;
      line-height: 1.7;
    }

    .hero-cta {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      margin-bottom: 36px;
    }

    .hero-highlights {
      display: flex;
      flex-wrap: wrap;
      gap: 20px;
    }

    .highlight-item {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 0.9rem;
      color: var(--text-muted);
      font-weight: 500;
    }

    .highlight-dot {
      width: 8px;
      height: 8px;
      background: #10b981;
      border-radius: 50%;
      display: inline-block;
    }

    /* Hero Data Visual Card (Pure CSS) */
    .hero-visual-card {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 16px;
      padding: 28px;
      box-shadow: 0 20px 25px -5px rgba(30, 64, 175, 0.08), 0 10px 10px -5px rgba(30, 64, 175, 0.04);
      position: relative;
    }

    .visual-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 20px;
      padding-bottom: 12px;
      border-bottom: 1px solid var(--border-color);
    }

    .visual-title {
      font-weight: 700;
      font-size: 1.05rem;
      color: var(--primary);
    }

    .visual-badge {
      font-size: 0.75rem;
      background: #dcfce7;
      color: #15803d;
      padding: 4px 8px;
      border-radius: 4px;
      font-weight: 600;
    }

    .visual-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 14px;
      margin-bottom: 20px;
    }

    .visual-stat {
      background: #f8fafc;
      padding: 14px;
      border-radius: 10px;
      border: 1px solid #f1f5f9;
    }

    .visual-stat .num {
      font-size: 1.4rem;
      font-weight: 800;
      color: var(--primary-bright);
      line-height: 1.2;
    }

    .visual-stat .lbl {
      font-size: 0.8rem;
      color: var(--text-muted);
      margin-top: 4px;
    }

    .visual-list {
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .visual-list-item {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 0.85rem;
      padding: 8px 12px;
      background: #f1f5f9;
      border-radius: 6px;
      color: var(--text-dark);
    }

    /* Grid Layouts */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 24px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
      gap: 20px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
      gap: 30px;
    }

    /* Cards */
    .card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-lg);
      border-color: #bfdbfe;
    }

    .card-icon {
      width: 48px;
      height: 48px;
      background: #eff6ff;
      color: var(--primary-bright);
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.5rem;
      font-weight: bold;
      margin-bottom: 16px;
    }

    .card-title {
      font-size: 1.2rem;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 10px;
    }

    .card-text {
      font-size: 0.95rem;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }

    .card-footer {
      margin-top: 16px;
      padding-top: 12px;
      border-top: 1px solid #f1f5f9;
      font-size: 0.85rem;
      color: var(--primary-bright);
      font-weight: 600;
    }

    /* Model Cloud / Badges */
    .model-badge-container {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-badge {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 0.85rem;
      font-weight: 600;
      color: var(--text-dark);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .model-badge:hover {
      background: var(--primary-bright);
      color: #ffffff;
      border-color: var(--primary-bright);
      transform: translateY(-2px);
    }

    /* Process Flow */
    .step-list {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
      gap: 20px;
      position: relative;
    }

    .step-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      text-align: center;
      position: relative;
    }

    .step-num {
      width: 36px;
      height: 36px;
      background: var(--primary-bright);
      color: #ffffff;
      border-radius: 50%;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      margin-bottom: 14px;
    }

    /* Media Showcase Images */
    .media-card {
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .media-card:hover {
      box-shadow: var(--shadow-lg);
      transform: translateY(-3px);
    }

    .media-card-img-wrap {
      width: 100%;
      background: #f1f5f9;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
    }

    .media-card-img-wrap img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
      transition: transform 0.5s ease;
    }

    .media-card:hover .media-card-img-wrap img {
      transform: scale(1.03);
    }

    .media-card-content {
      padding: 20px;
    }

    /* Comparison Table */
    .table-container {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow-x: auto;
      box-shadow: var(--shadow-sm);
    }

    .custom-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 600px;
    }

    .custom-table th,
    .custom-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
      font-size: 0.95rem;
    }

    .custom-table th {
      background: #f8fafc;
      color: var(--text-dark);
      font-weight: 700;
    }

    .custom-table tr:hover {
      background: #f8fafc;
    }

    .rating-badge {
      background: #fef3c7;
      color: #92400e;
      padding: 4px 8px;
      border-radius: 4px;
      font-weight: 700;
    }

    /* Reviews */
    .review-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .review-stars {
      color: #f59e0b;
      margin-bottom: 12px;
      font-size: 1rem;
    }

    .review-body {
      font-size: 0.95rem;
      color: var(--text-dark);
      line-height: 1.6;
      margin-bottom: 16px;
      font-style: italic;
    }

    .reviewer-info {
      display: flex;
      align-items: center;
      gap: 12px;
      padding-top: 12px;
      border-top: 1px solid #f1f5f9;
    }

    .reviewer-avatar {
      width: 40px;
      height: 40px;
      background: #e0e7ff;
      color: var(--primary);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
    }

    .reviewer-meta h4 {
      font-size: 0.95rem;
      color: var(--text-dark);
    }

    .reviewer-meta p {
      font-size: 0.8rem;
      color: var(--text-muted);
    }

    /* FAQ Accordion */
    .faq-list {
      max-width: 860px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      overflow: hidden;
      transition: var(--transition);
    }

    .faq-question {
      width: 100%;
      padding: 18px 20px;
      text-align: left;
      background: none;
      border: none;
      font-size: 1rem;
      font-weight: 600;
      color: var(--text-dark);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }

    .faq-question:hover {
      background-color: #f8fafc;
      color: var(--primary-bright);
    }

    .faq-answer {
      padding: 0 20px 18px;
      font-size: 0.95rem;
      color: var(--text-muted);
      line-height: 1.6;
      display: none;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    .faq-item.active .faq-toggle-icon {
      transform: rotate(45deg);
    }

    .faq-toggle-icon {
      font-size: 1.2rem;
      color: var(--text-muted);
      transition: transform 0.2s ease;
    }

    /* Articles Section */
    .articles-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 20px;
    }

    .article-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 20px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .article-item a {
      text-decoration: none;
      color: var(--text-dark);
      font-weight: 600;
      font-size: 1rem;
      line-height: 1.4;
      transition: color 0.2s ease;
    }

    .article-item a:hover {
      color: var(--primary-bright);
    }

    .article-meta {
      font-size: 0.8rem;
      color: var(--text-muted);
      margin-top: 14px;
    }

    /* Form & Contact */
    .form-box {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 16px;
      padding: 36px;
      box-shadow: var(--shadow-sm);
    }

    .form-group {
      margin-bottom: 20px;
    }

    .form-label {
      display: block;
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-dark);
      margin-bottom: 6px;
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      font-size: 0.95rem;
      background: #f8fafc;
      color: var(--text-dark);
      transition: var(--transition);
    }

    .form-control:focus {
      outline: none;
      border-color: var(--primary-bright);
      background: #ffffff;
      box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
    }

    textarea.form-control {
      resize: vertical;
      min-height: 110px;
    }

    .contact-info-card {
      background: linear-gradient(135deg, #1e40af, #1e3a8a);
      color: #ffffff;
      border-radius: 16px;
      padding: 36px;
      height: 100%;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .contact-info-card h3 {
      font-size: 1.4rem;
      margin-bottom: 20px;
      color: #ffffff;
    }

    .contact-item {
      margin-bottom: 18px;
      font-size: 0.95rem;
      color: #e0e7ff;
    }

    .contact-item strong {
      color: #ffffff;
      display: inline-block;
      width: 90px;
    }

    .qr-container {
      margin-top: 20px;
      background: rgba(255, 255, 255, 0.1);
      padding: 16px;
      border-radius: 12px;
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .qr-container img {
      width: 80px;
      height: 80px;
      border-radius: 6px;
      background: #ffffff;
    }

    /* Footer */
    .site-footer {
      background: #0f172a;
      color: #94a3b8;
      padding: 60px 0 24px;
      border-top: 1px solid #1e293b;
      margin-top: auto;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr repeat(3, 1fr);
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 1rem;
      margin-bottom: 16px;
      font-weight: 600;
    }

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .footer-links a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.9rem;
      transition: color 0.2s ease;
    }

    .footer-links a:hover {
      color: #ffffff;
    }

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
    }

    .friend-links a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.85rem;
      background: #1e293b;
      padding: 4px 10px;
      border-radius: 4px;
      transition: var(--transition);
    }

    .friend-links a:hover {
      color: #ffffff;
      background: var(--primary-bright);
    }

    .footer-bottom {
      padding-top: 24px;
      border-top: 1px solid #1e293b;
      display: flex;
      flex-wrap: wrap;
      justify-content: space-between;
      align-items: center;
      font-size: 0.85rem;
      color: #64748b;
    }

    /* Floating Tool */
    .float-widget {
      position: fixed;
      right: 20px;
      bottom: 30px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      z-index: 999;
    }

    .float-btn {
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: var(--primary-bright);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 12px rgba(37, 99, 235, 0.4);
      cursor: pointer;
      text-decoration: none;
      font-size: 1.2rem;
      transition: var(--transition);
      border: none;
    }

    .float-btn:hover {
      transform: scale(1.08);
      background: var(--primary);
    }

    /* Responsive */
    @media (max-width: 992px) {
      .hero-wrapper {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .menu-toggle {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.show {
        display: flex;
      }
      .nav-links li {
        width: 100%;
      }
      .nav-links li a {
        display: block;
        padding: 12px 16px;
      }
      .hero-content h1 {
        font-size: 2rem;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .section-title {
        font-size: 1.6rem;
      }
    }