:root {
      --primary: #10b981;
      --primary-dark: #059669;
      --primary-light: #ecfdf5;
      --primary-soft: #d1fae5;
      --accent: #14b8a6;
      --text-main: #1f2937;
      --text-muted: #4b5563;
      --text-light: #6b7280;
      --bg-page: #f8fafc;
      --bg-card: #ffffff;
      --border-color: #e2e8f0;
      --border-focus: #a7f3d0;
      --shadow-sm: 0 2px 8px rgba(16, 185, 129, 0.05);
      --shadow-md: 0 10px 25px -5px rgba(16, 185, 129, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
      --shadow-hover: 0 20px 30px -10px rgba(16, 185, 129, 0.16);
      --radius: 14px;
      --transition: all 0.28s ease;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.65;
      overflow-x: hidden;
    }

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

    .container {
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.94);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-color);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 74px;
    }

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

    .ai-page-logo {
      height: 42px;
      width: auto;
      display: block;
    }

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

    .nav-links li a {
      font-size: 14px;
      font-weight: 500;
      color: var(--text-muted);
      padding: 8px 12px;
      border-radius: 8px;
    }

    .nav-links li a:hover {
      color: var(--primary-dark);
      background: var(--primary-light);
    }

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-size: 14px;
      font-weight: 600;
      padding: 10px 22px;
      border-radius: 9999px;
      cursor: pointer;
      border: 1px solid transparent;
      transition: var(--transition);
      text-align: center;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(16, 185, 129, 0.35);
    }

    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(16, 185, 129, 0.45);
      color: #ffffff;
    }

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

    .btn-outline:hover {
      background: var(--primary-light);
      color: var(--primary-dark);
    }

    .btn-lg {
      padding: 14px 34px;
      font-size: 16px;
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
    }

    .mobile-menu-btn span {
      display: block;
      width: 22px;
      height: 2px;
      background: var(--text-main);
      margin: 5px 0;
      transition: var(--transition);
    }

    .section {
      padding: 72px 0;
      position: relative;
    }

    .section-alt {
      background: #f1f7f4;
    }

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

    .section-tag {
      display: inline-block;
      font-size: 13px;
      font-weight: 600;
      color: var(--primary-dark);
      background: var(--primary-soft);
      padding: 4px 14px;
      border-radius: 20px;
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .section-title {
      font-size: 32px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
      line-height: 1.35;
    }

    .section-desc {
      font-size: 16px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    .hero-section {
      padding: 90px 0 80px;
      background: radial-gradient(circle at 50% 10%, #d1fae5 0%, #f0fdf4 40%, var(--bg-page) 100%);
      text-align: center;
    }

    .hero-content {
      max-width: 860px;
      margin: 0 auto;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      font-size: 13px;
      font-weight: 600;
      padding: 6px 18px;
      background: rgba(255, 255, 255, 0.85);
      border: 1px solid var(--border-focus);
      border-radius: 9999px;
      color: var(--primary-dark);
      margin-bottom: 24px;
      box-shadow: var(--shadow-sm);
    }

    .hero-badge-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: var(--primary);
      box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.2);
    }

    .hero-title {
      font-size: 44px;
      font-weight: 800;
      line-height: 1.25;
      color: #064e3b;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-subtitle {
      font-size: 18px;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 36px;
      max-width: 720px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-cta-group {
      display: flex;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-top: 20px;
    }

    .stat-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      padding: 24px 16px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: var(--transition);
    }

    .stat-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: var(--border-focus);
    }

    .stat-num {
      font-size: 34px;
      font-weight: 800;
      color: var(--primary-dark);
      line-height: 1.1;
      margin-bottom: 6px;
    }

    .stat-label {
      font-size: 14px;
      color: var(--text-muted);
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

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

    .card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 28px;
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }

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

    .card-icon-box {
      width: 48px;
      height: 48px;
      border-radius: 12px;
      background: var(--primary-light);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary-dark);
    }

    .card-title {
      font-size: 18px;
      font-weight: 700;
      margin-bottom: 10px;
      color: var(--text-main);
    }

    .card-text {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }

    .model-tags-container {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-pill {
      background: #ffffff;
      border: 1px solid var(--border-color);
      padding: 8px 18px;
      border-radius: 9999px;
      font-size: 13px;
      font-weight: 500;
      color: var(--text-main);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .model-pill:hover {
      border-color: var(--primary);
      color: var(--primary-dark);
      background: var(--primary-light);
      transform: translateY(-2px);
    }

    .image-showcase-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
      margin-top: 36px;
    }

    .image-box {
      border-radius: var(--radius);
      overflow: hidden;
      border: 1px solid var(--border-color);
      background: #ffffff;
      box-shadow: var(--shadow-sm);
    }

    .image-box img {
      width: 100%;
      height: 240px;
      object-fit: cover;
      display: block;
      transition: var(--transition);
    }

    .image-box:hover img {
      transform: scale(1.03);
    }

    .image-caption {
      padding: 16px 20px;
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
      border-top: 1px solid var(--border-color);
      background: #fafafa;
    }

    .process-steps {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

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

    .step-index {
      font-size: 32px;
      font-weight: 800;
      color: var(--primary-soft);
      line-height: 1;
      margin-bottom: 12px;
    }

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

    .comparison-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 14px;
      min-width: 680px;
    }

    .comparison-table th,
    .comparison-table td {
      padding: 16px 22px;
      border-bottom: 1px solid var(--border-color);
    }

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

    .comparison-table tr:last-child td {
      border-bottom: none;
    }

    .highlight-col {
      background: var(--primary-light);
      font-weight: 600;
      color: var(--primary-dark);
    }

    .rating-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: #fef3c7;
      color: #92400e;
      padding: 4px 10px;
      border-radius: 6px;
      font-size: 12px;
      font-weight: 700;
    }

    .rating-score {
      font-size: 26px;
      font-weight: 800;
      color: #064e3b;
      margin-right: 6px;
    }

    .faq-accordion {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

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

    .faq-header {
      padding: 18px 24px;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      user-select: none;
      font-weight: 600;
      font-size: 16px;
      color: var(--text-main);
    }

    .faq-header:hover {
      background: #fcfdfd;
      color: var(--primary-dark);
    }

    .faq-icon {
      width: 20px;
      height: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: transform 0.25s ease;
      color: var(--primary);
    }

    .faq-item.active .faq-icon {
      transform: rotate(180deg);
    }

    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 24px;
      color: var(--text-muted);
      font-size: 14px;
      line-height: 1.7;
    }

    .faq-item.active .faq-content {
      padding: 0 24px 20px;
      max-height: 260px;
    }

    .reviews-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .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;
      box-shadow: var(--shadow-sm);
    }

    .review-author {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 18px;
    }

    .author-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--primary-soft);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--primary-dark);
      font-size: 15px;
    }

    .author-info h4 {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
    }

    .author-info p {
      font-size: 12px;
      color: var(--text-light);
    }

    .form-wrapper {
      max-width: 680px;
      margin: 0 auto;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 36px;
      box-shadow: var(--shadow-md);
    }

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

    .form-label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      font-size: 14px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      outline: none;
      transition: var(--transition);
      background: #fafafa;
    }

    .form-control:focus {
      background: #ffffff;
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.15);
    }

    textarea.form-control {
      resize: vertical;
      min-height: 100px;
    }

    .form-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 16px;
    }

    .articles-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
    }

    .article-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 10px;
      padding: 20px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      transition: var(--transition);
    }

    .article-item:hover {
      border-color: var(--primary);
      transform: translateY(-2px);
    }

    .article-item h4 {
      font-size: 15px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .article-link {
      font-size: 13px;
      color: var(--primary-dark);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    .site-footer {
      background: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 60px 0 24px;
      font-size: 14px;
      color: var(--text-muted);
    }

    .footer-top-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-col h5 {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 18px;
    }

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

    .footer-links a:hover {
      color: var(--primary-dark);
    }

    .qr-container {
      display: flex;
      align-items: center;
      gap: 16px;
      margin-top: 12px;
    }

    .qr-box {
      width: 100px;
      height: 100px;
      padding: 4px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 8px;
    }

    .qr-box img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }

    .friend-links {
      padding: 20px 0;
      border-top: 1px solid var(--border-color);
      border-bottom: 1px solid var(--border-color);
      margin-bottom: 24px;
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      align-items: center;
      font-size: 13px;
    }

    .friend-links a {
      color: var(--text-muted);
    }

    .friend-links a:hover {
      color: var(--primary-dark);
    }

    .footer-bottom {
      text-align: center;
      font-size: 13px;
      color: var(--text-light);
    }

    .float-contact {
      position: fixed;
      right: 20px;
      bottom: 24px;
      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;
      cursor: pointer;
      color: var(--primary-dark);
      transition: var(--transition);
      position: relative;
    }

    .float-btn:hover {
      background: var(--primary-light);
      transform: scale(1.06);
    }

    .float-tooltip {
      position: absolute;
      right: 58px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      padding: 10px;
      box-shadow: var(--shadow-md);
      display: none;
      width: 140px;
      text-align: center;
      font-size: 12px;
    }

    .float-tooltip img {
      width: 100%;
      height: auto;
      margin-bottom: 4px;
      border-radius: 4px;
    }

    .float-btn:hover .float-tooltip {
      display: block;
    }

    @media (max-width: 1024px) {
      .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3, .reviews-grid, .process-steps {
        grid-template-columns: repeat(2, 1fr);
      }
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-top-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .hero-title {
        font-size: 30px;
      }
      .section {
        padding: 48px 0;
      }
      .mobile-menu-btn {
        display: block;
      }
      .nav-links {
        position: absolute;
        top: 74px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
        display: none;
      }
      .nav-links.active {
        display: flex;
      }
      .grid-3, .grid-4, .reviews-grid, .process-steps, .image-showcase-grid, .articles-grid {
        grid-template-columns: 1fr;
      }
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
      .footer-top-grid {
        grid-template-columns: 1fr;
        gap: 30px;
      }
      .form-row {
        grid-template-columns: 1fr;
      }
      .header-actions .btn-outline {
        display: none;
      }
    }