:root {
      --primary: #2563eb;
      --primary-hover: #1d4ed8;
      --accent: #f97316;
      --accent-soft: #fff7ed;
      --bg-main: #f8fafc;
      --bg-card: #ffffff;
      --text-dark: #0f172a;
      --text-body: #334155;
      --text-muted: #64748b;
      --border-color: #e2e8f0;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 24px rgba(37,99,235,0.08);
      --shadow-lg: 0 16px 36px rgba(15,23,42,0.1);
      --radius: 12px;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
      background-color: var(--bg-main);
      color: var(--text-body);
      line-height: 1.65;
      overflow-x: hidden;
    }
    .container {
      width: 100%;
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }
    header.site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background-color: rgba(255, 255, 255, 0.96);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo-area {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
    }
    .logo-area .ai-page-logo {
      height: 40px;
      width: auto;
      display: block;
    }
    .brand-title {
      font-size: 1.35rem;
      font-weight: 800;
      color: var(--text-dark);
      letter-spacing: -0.5px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      list-style: none;
      gap: 0;
    }
    .nav-links li a {
      display: block;
      padding: 8px 12px;
      text-decoration: none;
      color: var(--text-body);
      font-size: 0.95rem;
      font-weight: 500;
      transition: color 0.2s ease;
    }
    .nav-links li a:hover {
      color: var(--primary);
    }
    .header-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-size: 0.95rem;
      font-weight: 600;
      padding: 10px 20px;
      border-radius: 8px;
      text-decoration: none;
      transition: all 0.25s ease;
      cursor: pointer;
      border: 1px solid transparent;
      line-height: 1.2;
    }
    .btn-primary {
      background-color: var(--primary);
      color: #ffffff;
      box-shadow: 0 4px 12px rgba(37,99,235,0.25);
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      box-shadow: 0 6px 16px rgba(37,99,235,0.35);
      transform: translateY(-1px);
    }
    .btn-accent {
      background-color: var(--accent);
      color: #ffffff;
      box-shadow: 0 4px 12px rgba(249,115,22,0.25);
    }
    .btn-accent:hover {
      background-color: #ea580c;
      transform: translateY(-1px);
    }
    .btn-outline {
      border-color: var(--border-color);
      background-color: #ffffff;
      color: var(--text-dark);
    }
    .btn-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      cursor: pointer;
      color: var(--text-dark);
      padding: 4px;
    }
    .hero-section {
      padding: 70px 0 60px;
      background: radial-gradient(circle at 50% 10%, #eff6ff 0%, #f8fafc 80%);
      border-bottom: 1px solid var(--border-color);
      text-align: center;
    }
    .hero-badge {
      display: inline-flex;
      align-items: center;
      padding: 6px 16px;
      border-radius: 9999px;
      background-color: #dbeafe;
      color: var(--primary);
      font-size: 0.875rem;
      font-weight: 600;
      margin-bottom: 24px;
    }
    .hero-title {
      font-size: 2.75rem;
      font-weight: 900;
      color: var(--text-dark);
      line-height: 1.25;
      margin-bottom: 20px;
      letter-spacing: -1px;
    }
    .hero-subtitle {
      max-width: 840px;
      margin: 0 auto 36px;
      font-size: 1.15rem;
      color: var(--text-body);
      line-height: 1.7;
    }
    .hero-cta {
      display: flex;
      justify-content: center;
      gap: 16px;
      margin-bottom: 48px;
      flex-wrap: wrap;
    }
    .hero-cta .btn-lg {
      padding: 14px 32px;
      font-size: 1.1rem;
      border-radius: 10px;
    }
    .model-pills {
      max-width: 980px;
      margin: 0 auto;
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 8px;
    }
    .model-pill {
      font-size: 0.8rem;
      background-color: #ffffff;
      color: var(--text-body);
      border: 1px solid var(--border-color);
      padding: 4px 10px;
      border-radius: 6px;
      font-weight: 500;
    }
    .metrics-bar {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-top: -30px;
      margin-bottom: 60px;
    }
    .metric-card {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s ease;
    }
    .metric-card:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow-md);
    }
    .metric-num {
      font-size: 2.2rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 6px;
      line-height: 1.1;
    }
    .metric-label {
      font-size: 0.9rem;
      color: var(--text-muted);
      font-weight: 500;
    }
    .section-wrap {
      padding: 60px 0;
    }
    .section-head {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 44px;
    }
    .section-tag {
      display: inline-block;
      font-size: 0.85rem;
      color: var(--primary);
      font-weight: 700;
      text-transform: uppercase;
      margin-bottom: 8px;
      letter-spacing: 1px;
    }
    .section-title {
      font-size: 2.1rem;
      font-weight: 800;
      color: var(--text-dark);
      line-height: 1.3;
      margin-bottom: 12px;
    }
    .section-desc {
      font-size: 1rem;
      color: var(--text-muted);
    }
    .intro-grid {
      display: grid;
      grid-template-columns: 1.1fr 0.9fr;
      gap: 36px;
      align-items: center;
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 40px;
      box-shadow: var(--shadow-sm);
    }
    .intro-text h3 {
      font-size: 1.6rem;
      color: var(--text-dark);
      margin-bottom: 16px;
      font-weight: 700;
    }
    .intro-text p {
      font-size: 1rem;
      color: var(--text-body);
      margin-bottom: 20px;
      line-height: 1.8;
    }
    .intro-points {
      list-style: none;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
    }
    .intro-points li {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 0.95rem;
      font-weight: 600;
      color: var(--text-dark);
    }
    .intro-points li::before {
      content: "✓";
      color: #10b981;
      font-weight: 900;
    }
    .intro-banner-wrap {
      border-radius: 8px;
      overflow: hidden;
      border: 1px solid var(--border-color);
      background-color: #f1f5f9;
    }
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 28px;
      transition: all 0.25s ease;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .service-card:hover {
      border-color: #bfdbfe;
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .service-card h4 {
      font-size: 1.25rem;
      color: var(--text-dark);
      margin-bottom: 12px;
      font-weight: 700;
    }
    .service-card p {
      font-size: 0.925rem;
      color: var(--text-body);
      line-height: 1.6;
      margin-bottom: 18px;
      flex-grow: 1;
    }
    .service-meta {
      font-size: 0.8rem;
      color: var(--primary);
      font-weight: 600;
      display: inline-block;
    }
    .flow-steps {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }
    .step-box {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      position: relative;
    }
    .step-idx {
      font-size: 2.2rem;
      font-weight: 900;
      color: #e2e8f0;
      line-height: 1;
      margin-bottom: 8px;
    }
    .step-box h4 {
      font-size: 1.15rem;
      color: var(--text-dark);
      margin-bottom: 8px;
      font-weight: 700;
    }
    .step-box p {
      font-size: 0.9rem;
      color: var(--text-muted);
    }
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow: hidden;
      display: flex;
      flex-direction: column;
    }
    .case-img-box {
      background-color: #f1f5f9;
      aspect-ratio: 16/9;
      overflow: hidden;
    }
    .case-img-box.square {
      aspect-ratio: 1/1;
    }
    .case-img-box img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: transform 0.3s ease;
    }
    .case-card:hover .case-img-box img {
      transform: scale(1.03);
    }
    .case-body {
      padding: 22px;
      flex-grow: 1;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .case-body h4 {
      font-size: 1.15rem;
      color: var(--text-dark);
      margin-bottom: 8px;
    }
    .case-body p {
      font-size: 0.9rem;
      color: var(--text-muted);
    }
    .review-score-banner {
      background: linear-gradient(135deg, #2563eb, #1e40af);
      color: #ffffff;
      border-radius: var(--radius);
      padding: 32px 40px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 30px;
    }
    .score-left h3 {
      font-size: 1.6rem;
      margin-bottom: 6px;
    }
    .score-left p {
      font-size: 0.95rem;
      opacity: 0.9;
    }
    .score-badge {
      text-align: right;
    }
    .score-num {
      font-size: 3rem;
      font-weight: 900;
      line-height: 1;
      color: #fef08a;
    }
    .score-stars {
      color: #fef08a;
      font-size: 1.2rem;
      letter-spacing: 2px;
    }
    .table-container {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow-x: auto;
      box-shadow: var(--shadow-sm);
    }
    .eval-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.925rem;
    }
    .eval-table th, .eval-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
    }
    .eval-table th {
      background-color: #f8fafc;
      font-weight: 700;
      color: var(--text-dark);
    }
    .eval-table tr:last-child td {
      border-bottom: none;
    }
    .eval-table tr:hover td {
      background-color: #f8fafc;
    }
    .highlight-col {
      background-color: #eff6ff;
      font-weight: 600;
      color: var(--primary);
    }
    .comments-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .comment-card {
      background-color: var(--bg-card);
      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;
    }
    .comment-card p {
      font-size: 0.925rem;
      color: var(--text-body);
      line-height: 1.7;
      margin-bottom: 16px;
      font-style: italic;
    }
    .commenter {
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-top: 1px solid var(--border-color);
      padding-top: 12px;
    }
    .commenter-name {
      font-weight: 700;
      color: var(--text-dark);
      font-size: 0.9rem;
    }
    .commenter-role {
      font-size: 0.8rem;
      color: var(--text-muted);
    }
    .faq-list {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }
    .faq-item {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 8px;
      overflow: hidden;
      transition: border-color 0.2s;
    }
    .faq-item:hover {
      border-color: #cbd5e1;
    }
    .faq-question {
      padding: 18px 24px;
      font-weight: 700;
      color: var(--text-dark);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      user-select: none;
    }
    .faq-question::after {
      content: "+";
      font-size: 1.3rem;
      color: var(--primary);
      transition: transform 0.2s;
    }
    .faq-item.active .faq-question::after {
      transform: rotate(45deg);
    }
    .faq-answer {
      display: none;
      padding: 0 24px 20px;
      font-size: 0.95rem;
      color: var(--text-body);
      line-height: 1.7;
      border-top: 1px solid transparent;
    }
    .faq-item.active .faq-answer {
      display: block;
      border-top-color: #f1f5f9;
    }
    .articles-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
      margin-bottom: 24px;
    }
    .article-item {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 20px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .article-item a {
      text-decoration: none;
      color: var(--text-dark);
      font-weight: 700;
      font-size: 1rem;
      display: block;
      margin-bottom: 10px;
      line-height: 1.5;
    }
    .article-item a:hover {
      color: var(--primary);
    }
    .article-meta {
      font-size: 0.8rem;
      color: var(--text-muted);
    }
    .contact-container {
      display: grid;
      grid-template-columns: 1.1fr 0.9fr;
      gap: 36px;
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 40px;
      box-shadow: var(--shadow-md);
    }
    .form-group {
      margin-bottom: 16px;
    }
    .form-group label {
      display: block;
      font-size: 0.875rem;
      font-weight: 600;
      color: var(--text-dark);
      margin-bottom: 6px;
    }
    .form-control {
      width: 100%;
      padding: 10px 14px;
      border: 1px solid var(--border-color);
      border-radius: 6px;
      font-size: 0.95rem;
      color: var(--text-dark);
      background-color: #ffffff;
      outline: none;
      transition: border-color 0.2s;
    }
    .form-control:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(37,99,235,0.12);
    }
    textarea.form-control {
      resize: vertical;
      min-height: 110px;
    }
    .contact-info-wrap {
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .contact-items {
      display: flex;
      flex-direction: column;
      gap: 16px;
      margin-bottom: 24px;
    }
    .contact-item {
      display: flex;
      flex-direction: column;
    }
    .contact-item span.lbl {
      font-size: 0.8rem;
      color: var(--text-muted);
      font-weight: 600;
    }
    .contact-item span.val {
      font-size: 1.05rem;
      color: var(--text-dark);
      font-weight: 700;
    }
    .qr-box {
      border: 1px solid var(--border-color);
      border-radius: 8px;
      padding: 16px;
      background-color: #f8fafc;
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .qr-box img {
      width: 90px;
      height: 90px;
      object-fit: cover;
      border-radius: 4px;
    }
    .qr-desc h5 {
      font-size: 1rem;
      color: var(--text-dark);
      margin-bottom: 4px;
    }
    .qr-desc p {
      font-size: 0.825rem;
      color: var(--text-muted);
    }
    footer.site-footer {
      background-color: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 48px 0 24px;
      color: var(--text-body);
    }
    .footer-top {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 36px;
    }
    .footer-brand h4 {
      font-size: 1.25rem;
      color: var(--text-dark);
      margin-bottom: 12px;
      font-weight: 800;
    }
    .footer-brand p {
      font-size: 0.9rem;
      color: var(--text-muted);
      line-height: 1.7;
      max-width: 440px;
    }
    .footer-links h5 {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 14px;
    }
    .footer-links ul {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }
    .footer-links ul li a {
      color: var(--text-muted);
      text-decoration: none;
      font-size: 0.875rem;
      transition: color 0.2s;
    }
    .footer-links ul li a:hover {
      color: var(--primary);
    }
    .footer-friend-links {
      border-top: 1px solid var(--border-color);
      padding-top: 20px;
      margin-bottom: 24px;
    }
    .friend-links-list {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      list-style: none;
    }
    .friend-links-list a {
      color: var(--text-muted);
      font-size: 0.85rem;
      text-decoration: none;
    }
    .friend-links-list a:hover {
      color: var(--primary);
    }
    .footer-bottom {
      border-top: 1px solid var(--border-color);
      padding-top: 20px;
      text-align: center;
      font-size: 0.85rem;
      color: var(--text-muted);
    }
    .floating-kefu {
      position: fixed;
      right: 20px;
      bottom: 80px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }
    .float-btn {
      width: 50px;
      height: 50px;
      border-radius: 50%;
      background-color: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 14px rgba(37,99,235,0.3);
      cursor: pointer;
      text-decoration: none;
      font-size: 0.8rem;
      font-weight: 700;
      transition: transform 0.2s ease;
    }
    .float-btn:hover {
      transform: scale(1.08);
      background-color: var(--primary-hover);
    }
    @media (max-width: 992px) {
      .services-grid, .comments-grid, .cases-grid, .articles-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .metrics-bar, .flow-steps {
        grid-template-columns: repeat(2, 1fr);
      }
      .intro-grid, .contact-container, .footer-top {
        grid-template-columns: 1fr;
      }
      .hero-title {
        font-size: 2.1rem;
      }
    }
    @media (max-width: 768px) {
      .menu-toggle {
        display: block;
      }
      .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background-color: #ffffff;
        border-bottom: 1px solid var(--border-color);
        padding: 16px 20px;
        box-shadow: var(--shadow-md);
      }
      .nav-links.active {
        display: flex;
      }
      .nav-links li a {
        padding: 10px 0;
      }
      .services-grid, .comments-grid, .cases-grid, .articles-grid, .metrics-bar, .flow-steps {
        grid-template-columns: 1fr;
      }
      .hero-title {
        font-size: 1.75rem;
      }
      .hero-section {
        padding: 40px 0;
      }
      .review-score-banner {
        flex-direction: column;
        text-align: center;
        gap: 16px;
      }
      .score-badge {
        text-align: center;
      }
    }