:root {
      --primary: #0a4cd2;
      --primary-dark: #002f87;
      --primary-light: #e8f0fe;
      --accent: #00b4d8;
      --text-main: #1e293b;
      --text-muted: #64748b;
      --bg-base: #f8fafc;
      --card-bg: #ffffff;
      --border-color: #e2e8f0;
      --shadow-sm: 0 2px 8px rgba(10, 76, 210, 0.05);
      --shadow-md: 0 8px 24px rgba(10, 76, 210, 0.08);
      --shadow-lg: 0 16px 36px rgba(10, 76, 210, 0.12);
      --radius: 12px;
      --container-max: 1200px;
    }

    * {
      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-base);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

    a {
      color: inherit;
      text-decoration: none;
    }

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

    /* 顶部导航 */
    .site-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);
      transition: all 0.3s ease;
    }

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

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

    .brand-wrap .ai-page-logo {
      height: 38px;
      width: auto;
      display: block;
    }

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

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-main);
      padding: 8px 12px;
      border-radius: 6px;
      transition: color 0.2s ease, background-color 0.2s ease;
      display: inline-block;
    }

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

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 22px;
      font-size: 15px;
      font-weight: 600;
      border-radius: 8px;
      cursor: pointer;
      transition: all 0.25s ease;
      border: 1px solid transparent;
      text-align: center;
    }

    .btn-primary {
      background-color: var(--primary);
      color: #ffffff;
      box-shadow: 0 4px 12px rgba(10, 76, 210, 0.25);
    }

    .btn-primary:hover {
      background-color: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 6px 16px rgba(10, 76, 210, 0.35);
    }

    .btn-outline {
      border-color: var(--primary);
      color: var(--primary);
      background: transparent;
    }

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

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      cursor: pointer;
      color: var(--text-main);
      padding: 8px;
    }

    /* 首屏纯CSS科技风格，无图片 */
    .hero-section {
      background: linear-gradient(135deg, #ffffff 0%, #edf4ff 50%, #e0edff 100%);
      padding: 80px 0 60px;
      border-bottom: 1px solid var(--border-color);
      position: relative;
      overflow: hidden;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      padding: 6px 16px;
      background-color: var(--primary-light);
      border: 1px solid rgba(10, 76, 210, 0.2);
      border-radius: 30px;
      color: var(--primary);
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 24px;
    }

    .hero-content {
      max-width: 820px;
      margin: 0 auto;
      text-align: center;
    }

    .hero-title {
      font-size: 40px;
      font-weight: 800;
      color: #0b1f48;
      line-height: 1.25;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-desc {
      font-size: 18px;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 36px;
    }

    .hero-btns {
      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: 20px;
    }

    .stat-card {
      background: rgba(255, 255, 255, 0.85);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px 16px;
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: transform 0.3s ease;
    }

    .stat-card:hover {
      transform: translateY(-4px);
    }

    .stat-val {
      font-size: 32px;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 4px;
    }

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

    /* 通用Section */
    .section-wrap {
      padding: 70px 0;
      border-bottom: 1px solid var(--border-color);
      background-color: var(--bg-base);
    }

    .section-wrap.alt-bg {
      background-color: #ffffff;
    }

    .section-header {
      text-align: center;
      max-width: 720px;
      margin: 0 auto 50px;
    }

    .section-subtitle {
      color: var(--primary);
      font-size: 14px;
      font-weight: 700;
      letter-spacing: 1px;
      text-transform: uppercase;
      margin-bottom: 10px;
      display: block;
    }

    .section-title {
      font-size: 30px;
      font-weight: 700;
      color: #0b1f48;
      margin-bottom: 14px;
    }

    .section-intro {
      font-size: 16px;
      color: var(--text-muted);
    }

    /* 平台介绍 */
    .intro-grid {
      display: grid;
      grid-template-columns: 1.2fr 1fr;
      gap: 40px;
      align-items: center;
    }

    .intro-text-box h3 {
      font-size: 24px;
      color: var(--primary-dark);
      margin-bottom: 18px;
    }

    .intro-text-box p {
      color: var(--text-muted);
      margin-bottom: 16px;
      font-size: 15px;
    }

    .intro-feature-list {
      list-style: none;
      margin-top: 24px;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
    }

    .intro-feature-list li {
      font-size: 14px;
      color: var(--text-main);
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .intro-feature-list li::before {
      content: "✓";
      color: var(--primary);
      font-weight: bold;
    }

    .intro-media-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 20px;
      box-shadow: var(--shadow-md);
    }

    .media-container {
      width: 100%;
      border-radius: 8px;
      overflow: hidden;
      margin-bottom: 16px;
      background: #f1f5f9;
    }

    .media-container img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
    }

    /* 服务卡片网格 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 30px 24px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .service-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(10, 76, 210, 0.4);
    }

    .service-icon-box {
      width: 50px;
      height: 50px;
      border-radius: 10px;
      background-color: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 22px;
      font-weight: 700;
      margin-bottom: 20px;
    }

    .service-card h4 {
      font-size: 20px;
      color: #0b1f48;
      margin-bottom: 12px;
    }

    .service-card p {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      margin-bottom: 20px;
    }

    .tag-row {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
    }

    .tag-item {
      font-size: 12px;
      padding: 4px 10px;
      background: var(--bg-base);
      border: 1px solid var(--border-color);
      border-radius: 20px;
      color: var(--text-muted);
    }

    /* 场景与模型标签云 */
    .models-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      justify-content: center;
      margin-top: 30px;
    }

    .model-chip {
      background: #ffffff;
      border: 1px solid var(--border-color);
      padding: 8px 18px;
      border-radius: 30px;
      font-size: 14px;
      font-weight: 500;
      color: var(--text-main);
      box-shadow: var(--shadow-sm);
      transition: all 0.2s;
    }

    .model-chip:hover {
      border-color: var(--primary);
      color: var(--primary);
      background-color: var(--primary-light);
    }

    /* 流程步骤 */
    .steps-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      position: relative;
    }

    .step-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 28px 20px;
      text-align: center;
      box-shadow: var(--shadow-sm);
    }

    .step-num {
      width: 44px;
      height: 44px;
      line-height: 44px;
      background: var(--primary);
      color: #ffffff;
      border-radius: 50%;
      margin: 0 auto 16px;
      font-weight: 700;
      font-size: 18px;
    }

    .step-card h4 {
      font-size: 18px;
      margin-bottom: 10px;
      color: #0b1f48;
    }

    .step-card p {
      font-size: 13px;
      color: var(--text-muted);
    }

    /* 对比表格 */
    .table-container {
      width: 100%;
      overflow-x: auto;
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .custom-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 680px;
    }

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

    .custom-table th {
      background-color: #f1f5f9;
      color: #0b1f48;
      font-weight: 700;
    }

    .custom-table tr:hover td {
      background-color: var(--bg-base);
    }

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

    .score-badge {
      display: inline-block;
      padding: 4px 10px;
      background: #e0f2fe;
      color: #0369a1;
      border-radius: 6px;
      font-weight: bold;
      font-size: 13px;
    }

    /* 案例展示 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 30px;
    }

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

    .case-img-box {
      width: 100%;
      background: #e2e8f0;
    }

    .case-img-box img {
      width: 100%;
      height: auto;
      display: block;
    }

    .case-content {
      padding: 24px;
    }

    .case-content h4 {
      font-size: 20px;
      margin-bottom: 10px;
      color: #0b1f48;
    }

    .case-content p {
      font-size: 14px;
      color: var(--text-muted);
      margin-bottom: 16px;
    }

    /* 用户评论 */
    .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;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .review-text {
      font-size: 14px;
      color: var(--text-main);
      line-height: 1.7;
      margin-bottom: 20px;
      font-style: italic;
    }

    .reviewer-info {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid var(--border-color);
      padding-top: 14px;
    }

    .reviewer-avatar {
      width: 42px;
      height: 42px;
      border-radius: 50%;
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: bold;
      font-size: 14px;
    }

    .reviewer-meta h5 {
      font-size: 15px;
      color: #0b1f48;
    }

    .reviewer-meta span {
      font-size: 12px;
      color: var(--text-muted);
    }

    /* FAQ 折叠面板 */
    .faq-container {
      max-width: 860px;
      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;
      box-shadow: var(--shadow-sm);
    }

    .faq-question {
      padding: 18px 24px;
      font-size: 16px;
      font-weight: 600;
      color: #0b1f48;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
      transition: background 0.2s;
    }

    .faq-question:hover {
      background: #f8fafc;
    }

    .faq-icon {
      font-size: 20px;
      color: var(--primary);
      transition: transform 0.3s;
    }

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

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

    .faq-item.active .faq-answer {
      max-height: 300px;
      padding: 0 24px 20px;
    }

    /* 文章与资讯列表 */
    .articles-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .article-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 20px;
      box-shadow: var(--shadow-sm);
    }

    .article-card h4 {
      font-size: 16px;
      margin-bottom: 8px;
    }

    .article-card a {
      color: var(--primary-dark);
      transition: color 0.2s;
    }

    .article-card a:hover {
      color: var(--primary);
      text-decoration: underline;
    }

    .article-meta {
      font-size: 13px;
      color: var(--text-muted);
      display: flex;
      gap: 12px;
    }

    /* 表单与联系模块 */
    .contact-layout {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: start;
    }

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

    .form-control {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      font-size: 14px;
      color: var(--text-main);
      background-color: #ffffff;
      transition: border-color 0.2s;
    }

    .form-control:focus {
      outline: none;
      border-color: var(--primary);
    }

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

    .contact-card-box {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 36px;
      box-shadow: var(--shadow-sm);
    }

    .contact-card-box h3 {
      font-size: 22px;
      color: #0b1f48;
      margin-bottom: 20px;
    }

    .contact-item-row {
      display: flex;
      margin-bottom: 18px;
      gap: 12px;
      font-size: 15px;
      align-items: center;
    }

    .contact-item-label {
      font-weight: 600;
      color: var(--text-muted);
      min-width: 90px;
    }

    .qr-container {
      margin-top: 24px;
      text-align: center;
      display: inline-block;
      padding: 16px;
      background: var(--bg-base);
      border: 1px solid var(--border-color);
      border-radius: 12px;
    }

    .qr-container img {
      width: 130px;
      height: 130px;
      display: block;
      margin: 0 auto 8px;
      border-radius: 6px;
    }

    .qr-label {
      font-size: 13px;
      color: var(--text-muted);
    }

    /* 友情链接与页脚 */
    .site-footer {
      background-color: #0b1528;
      color: #cbd5e1;
      padding: 60px 0 30px;
      font-size: 14px;
      border-top: 1px solid #1e293b;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
      margin-bottom: 40px;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 16px;
      margin-bottom: 20px;
    }

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

    .footer-links a {
      color: #94a3b8;
      transition: color 0.2s;
    }

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

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

    .friend-links-wrap a {
      color: #94a3b8;
      transition: color 0.2s;
    }

    .friend-links-wrap a:hover {
      color: var(--accent);
    }

    .footer-bottom {
      border-top: 1px solid #1e293b;
      padding-top: 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 16px;
      color: #64748b;
      font-size: 13px;
    }

    /* 浮动组件 */
    .floating-widget {
      position: fixed;
      right: 24px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      background: var(--primary);
      color: #ffffff;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
      cursor: pointer;
      border: none;
      transition: transform 0.2s;
    }

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

    /* 响应式适配 */
    @media (max-width: 992px) {
      .hero-stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .cards-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .steps-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .reviews-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .intro-grid {
        grid-template-columns: 1fr;
      }
      .contact-layout {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .mobile-menu-btn {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow-md);
        border-bottom: 1px solid var(--border-color);
      }
      .nav-links.show {
        display: flex;
      }
      .hero-title {
        font-size: 28px;
      }
      .cards-grid,
      .steps-grid,
      .case-grid,
      .reviews-grid,
      .articles-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .floating-widget {
        right: 16px;
        bottom: 20px;
      }
    }