:root {
      --rb-red: #ff4d4f;
      --rb-orange: #fa8c16;
      --rb-yellow: #fadb14;
      --rb-green: #52c41a;
      --rb-cyan: #13c2c2;
      --rb-blue: #1890ff;
      --rb-purple: #722ed1;
      --rainbow-grad: linear-gradient(135deg, #ff4d4f 0%, #fa8c16 20%, #fadb14 40%, #52c41a 60%, #13c2c2 80%, #1890ff 100%);
      --bg-page: #f8fafc;
      --bg-card: #ffffff;
      --text-main: #1e293b;
      --text-muted: #64748b;
      --border-color: #e2e8f0;
      --primary: #2563eb;
      --primary-hover: #1d4ed8;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.06);
      --shadow-lg: 0 16px 36px rgba(0,0,0,0.08);
      --radius: 12px;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
      color: var(--text-main);
      background-color: var(--bg-page);
    }
    body {
      line-height: 1.6;
      overflow-x: hidden;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
      background: radial-gradient(circle at 10% 10%, rgba(255, 77, 79, 0.03) 0%, transparent 40%),
                  radial-gradient(circle at 90% 20%, rgba(24, 144, 255, 0.04) 0%, transparent 40%),
                  radial-gradient(circle at 50% 80%, rgba(82, 196, 26, 0.03) 0%, transparent 40%),
                  #f8fafc;
    }
    .container {
      width: 100%;
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }
    /* Rainbow top bar */
    .rainbow-top-bar {
      height: 4px;
      background: var(--rainbow-grad);
      width: 100%;
    }
    /* Header */
    header.site-header {
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
      position: sticky;
      top: 0;
      z-index: 1000;
    }
    .nav-wrapper {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .brand-area {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .brand-area img.ai-page-logo {
      height: 40px;
      width: auto;
      display: block;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 0;
      list-style: none;
    }
    .nav-links li a {
      text-decoration: none;
      color: var(--text-main);
      font-size: 14px;
      font-weight: 500;
      padding: 8px 12px;
      border-radius: 6px;
      transition: all 0.25s ease;
      display: inline-block;
    }
    .nav-links li a:hover {
      color: var(--primary);
      background: rgba(37, 99, 235, 0.05);
    }
    .nav-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 20px;
      font-size: 14px;
      font-weight: 600;
      border-radius: 8px;
      text-decoration: none;
      cursor: pointer;
      border: 1px solid transparent;
      transition: all 0.25s ease;
    }
    .btn-rainbow {
      background: var(--rainbow-grad);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(250, 140, 22, 0.25);
    }
    .btn-rainbow:hover {
      opacity: 0.95;
      transform: translateY(-1px);
      box-shadow: 0 6px 18px rgba(250, 140, 22, 0.35);
    }
    .btn-primary {
      background-color: var(--primary);
      color: #ffffff;
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      transform: translateY(-1px);
    }
    .btn-outline {
      border-color: var(--border-color);
      background: #ffffff;
      color: var(--text-main);
    }
    .btn-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
    }
    .mobile-menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      cursor: pointer;
      color: var(--text-main);
    }

    /* Section Global */
    section {
      padding: 64px 0;
    }
    .section-header {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 48px auto;
    }
    .section-tag {
      display: inline-block;
      padding: 4px 12px;
      font-size: 12px;
      font-weight: 600;
      color: var(--primary);
      background: rgba(37, 99, 235, 0.08);
      border-radius: 20px;
      margin-bottom: 12px;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    .section-title {
      font-size: 28px;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 12px;
      line-height: 1.3;
    }
    .section-subtitle {
      font-size: 15px;
      color: var(--text-muted);
    }

    /* Hero Section (No Images as per rule) */
    .hero-section {
      padding: 80px 0 60px 0;
      position: relative;
    }
    .hero-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 20px;
      padding: 48px;
      box-shadow: var(--shadow-md);
      position: relative;
      overflow: hidden;
    }
    .hero-card::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 6px;
      background: var(--rainbow-grad);
    }
    .hero-content {
      text-align: center;
      max-width: 860px;
      margin: 0 auto;
    }
    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      padding: 6px 16px;
      background: linear-gradient(90deg, rgba(255, 77, 79, 0.08), rgba(24, 144, 255, 0.08));
      border-radius: 30px;
      font-size: 13px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 24px;
      border: 1px solid rgba(24, 144, 255, 0.15);
    }
    .hero-title {
      font-size: 38px;
      font-weight: 900;
      line-height: 1.25;
      margin-bottom: 20px;
      color: #0f172a;
    }
    .hero-desc {
      font-size: 16px;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 32px;
    }
    .hero-btn-group {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 16px;
      margin-bottom: 40px;
    }
    .hero-btn-group .btn {
      padding: 14px 28px;
      font-size: 16px;
    }
    .hero-model-tags {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 8px;
      padding-top: 24px;
      border-top: 1px dashed var(--border-color);
    }
    .model-pill {
      font-size: 12px;
      padding: 4px 10px;
      background: #f1f5f9;
      border-radius: 6px;
      color: #475569;
      font-weight: 500;
    }

    /* Stats Grid */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-top: 32px;
    }
    .stat-card {
      background: #ffffff;
      padding: 24px;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      text-align: center;
    }
    .stat-val {
      font-size: 32px;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 4px;
    }
    .stat-title {
      font-size: 13px;
      color: var(--text-muted);
    }

    /* Grid Layouts */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
      align-items: center;
    }

    /* Cards */
    .feature-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: #cbd5e1;
    }
    .feature-icon-bar {
      width: 40px;
      height: 4px;
      background: var(--rainbow-grad);
      border-radius: 2px;
      margin-bottom: 16px;
    }
    .feature-card h3 {
      font-size: 18px;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--text-main);
    }
    .feature-card p {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }
    .card-footer-tag {
      margin-top: 16px;
      font-size: 12px;
      color: var(--primary);
      font-weight: 600;
    }

    /* Media Visual section */
    .media-card-wrap {
      border-radius: var(--radius);
      overflow: hidden;
      border: 1px solid var(--border-color);
      background: #ffffff;
      box-shadow: var(--shadow-sm);
    }
    .media-card-wrap img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
    }
    .media-card-desc {
      padding: 16px 20px;
    }

    /* Compare Table & Evaluation */
    .eval-box {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 32px;
      box-shadow: var(--shadow-md);
    }
    .eval-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 16px;
      margin-bottom: 24px;
      padding-bottom: 20px;
      border-bottom: 1px solid var(--border-color);
    }
    .score-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: #fff7e6;
      border: 1px solid #ffd591;
      padding: 8px 16px;
      border-radius: 8px;
    }
    .score-number {
      font-size: 24px;
      font-weight: 900;
      color: #d46b08;
    }
    .table-container {
      width: 100%;
      overflow-x: auto;
    }
    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 14px;
    }
    .compare-table th, .compare-table td {
      padding: 14px 16px;
      border-bottom: 1px solid var(--border-color);
    }
    .compare-table th {
      background-color: #f8fafc;
      color: var(--text-main);
      font-weight: 700;
    }
    .compare-table tr:hover td {
      background-color: #f1f5f9;
    }
    .highlight-col {
      background-color: rgba(37, 99, 235, 0.03);
      font-weight: 600;
      color: var(--primary);
    }

    /* Process Workflow */
    .process-timeline {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      position: relative;
    }
    .process-step {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      position: relative;
    }
    .step-num {
      width: 32px;
      height: 32px;
      background: var(--rainbow-grad);
      color: #ffffff;
      font-weight: 800;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 50%;
      margin-bottom: 16px;
      font-size: 14px;
    }
    .step-title {
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 8px;
    }
    .step-desc {
      font-size: 13px;
      color: var(--text-muted);
    }

    /* FAQ Accordion */
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
    }
    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow: hidden;
      transition: all 0.25s ease;
    }
    .faq-question {
      padding: 16px 20px;
      font-size: 15px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: #ffffff;
    }
    .faq-question:hover {
      background: #f8fafc;
    }
    .faq-answer {
      padding: 0 20px 16px 20px;
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-item.active {
      border-color: var(--primary);
    }

    /* Testimonials */
    .testimonial-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .testi-header {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 14px;
    }
    .testi-avatar-placeholder {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: linear-gradient(135deg, #1890ff, #13c2c2);
      color: #fff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: bold;
      font-size: 16px;
    }
    .testi-name {
      font-size: 15px;
      font-weight: 700;
    }
    .testi-role {
      font-size: 12px;
      color: var(--text-muted);
    }
    .testi-text {
      font-size: 14px;
      color: #334155;
      line-height: 1.6;
    }

    /* Form & Contact */
    .contact-wrapper {
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      gap: 40px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 20px;
      padding: 40px;
      box-shadow: var(--shadow-md);
    }
    .contact-info-col h3 {
      font-size: 22px;
      font-weight: 800;
      margin-bottom: 16px;
    }
    .info-list {
      list-style: none;
      margin-top: 20px;
    }
    .info-list li {
      margin-bottom: 12px;
      font-size: 14px;
      color: var(--text-muted);
    }
    .qr-card {
      margin-top: 24px;
      padding: 16px;
      background: #f8fafc;
      border: 1px dashed var(--border-color);
      border-radius: var(--radius);
      display: inline-block;
      text-align: center;
    }
    .qr-card img {
      width: 130px;
      height: 130px;
      display: block;
      margin: 0 auto 8px auto;
      border-radius: 6px;
    }
    .custom-form .form-group {
      margin-bottom: 16px;
    }
    .custom-form label {
      display: block;
      font-size: 13px;
      font-weight: 600;
      margin-bottom: 6px;
    }
    .custom-form input, .custom-form select, .custom-form textarea {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      font-size: 14px;
      background: #ffffff;
      color: var(--text-main);
      outline: none;
      transition: border-color 0.2s;
    }
    .custom-form input:focus, .custom-form select:focus, .custom-form textarea:focus {
      border-color: var(--primary);
    }

    /* Article list */
    .article-links-box {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
    }
    .article-list {
      list-style: none;
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 12px;
    }
    .article-list li a {
      color: var(--text-main);
      text-decoration: none;
      font-size: 14px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .article-list li a:hover {
      color: var(--primary);
    }

    /* Footer */
    footer.site-footer {
      background-color: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 48px 0 24px 0;
      margin-top: 40px;
      color: var(--text-muted);
      font-size: 13px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
      margin-bottom: 36px;
    }
    .footer-col h4 {
      color: var(--text-main);
      font-size: 15px;
      margin-bottom: 16px;
      font-weight: 700;
    }
    .footer-col ul {
      list-style: none;
    }
    .footer-col ul li {
      margin-bottom: 8px;
    }
    .footer-col ul li a {
      color: var(--text-muted);
      text-decoration: none;
      transition: color 0.2s;
    }
    .footer-col ul li a:hover {
      color: var(--primary);
    }
    .friend-links-row {
      padding-top: 20px;
      border-top: 1px solid var(--border-color);
      margin-bottom: 20px;
      display: flex;
      flex-wrap: wrap;
      gap: 14px;
      align-items: center;
    }
    .friend-links-row span {
      font-weight: 600;
      color: var(--text-main);
    }
    .friend-links-row a {
      color: var(--text-muted);
      text-decoration: none;
    }
    .friend-links-row a:hover {
      color: var(--primary);
    }
    .footer-bottom {
      text-align: center;
      padding-top: 20px;
      border-top: 1px solid var(--border-color);
      font-size: 12px;
      color: #94a3b8;
    }

    /* Float Service */
    .float-service-bar {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }
    .float-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #ffffff;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-md);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--text-main);
      text-decoration: none;
      font-size: 20px;
      cursor: pointer;
      transition: all 0.2s;
    }
    .float-btn:hover {
      background: var(--primary);
      color: #ffffff;
      transform: translateY(-2px);
    }

    /* Responsive */
    @media (max-width: 992px) {
      .grid-4, .process-timeline {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .contact-wrapper {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 768px) {
      .nav-links, .nav-actions .btn-outline {
        display: none;
      }
      .nav-links.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        border-bottom: 1px solid var(--border-color);
        padding: 16px 20px;
        box-shadow: var(--shadow-md);
      }
      .nav-links.active li {
        width: 100%;
      }
      .nav-links.active li a {
        display: block;
        padding: 10px 0;
      }
      .mobile-menu-toggle {
        display: block;
      }
      .hero-title {
        font-size: 26px;
      }
      .hero-card {
        padding: 28px 16px;
      }
      .grid-3, .grid-4, .grid-2, .faq-grid, .article-list, .stats-grid, .process-timeline {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }