/* 全局变量与渐变青科技风配色 */
    :root {
      --primary-teal: #00a896;
      --primary-dark: #028090;
      --accent-cyan: #05668d;
      --gradient-start: #0d2b35;
      --gradient-end: #004b56;
      --bg-page: #f4f9f9;
      --bg-surface: #ffffff;
      --bg-card: #ffffff;
      --text-main: #1e293b;
      --text-muted: #64748b;
      --text-light: #475569;
      --border-color: #ccedd7;
      --border-light: #e2e8f0;
      --shadow-sm: 0 2px 8px rgba(0, 168, 150, 0.08);
      --shadow-lg: 0 12px 32px rgba(2, 128, 144, 0.12);
      --radius: 10px;
    }

    * {
      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;
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.6;
    }

    body {
      background-color: var(--bg-page);
      color: var(--text-main);
      overflow-x: hidden;
    }

    /* 统一居中容器 */
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
      width: 100%;
    }

    /* 顶部导航 */
    .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);
    }

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

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

    .ai-page-logo {
      height: 40px;
      width: auto;
      display: block;
    }

    .ai-page-home-link {
      font-weight: 600;
      color: var(--primary-dark);
      text-decoration: none;
      font-size: 15px;
      padding: 4px 10px;
      background: #e6f7f5;
      border-radius: 6px;
      transition: all 0.3s;
    }

    .ai-page-home-link:hover {
      background: var(--primary-teal);
      color: #fff;
    }

    .nav-links {
      gap: 0; /* 必须显式设为 0 */
      display: flex;
      align-items: center;
      list-style: none;
    }

    .nav-links li a {
      text-decoration: none;
      color: var(--text-main);
      font-size: 14px;
      font-weight: 500;
      padding: 8px 12px;
      transition: color 0.2s;
    }

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

    .header-btn {
      background: linear-gradient(135deg, var(--primary-teal), var(--primary-dark));
      color: #fff;
      padding: 9px 20px;
      border-radius: 6px;
      text-decoration: none;
      font-weight: 600;
      font-size: 14px;
      transition: transform 0.2s, box-shadow 0.2s;
    }

    .header-btn:hover {
      transform: translateY(-2px);
      box-shadow: 0 4px 12px rgba(0, 168, 150, 0.3);
    }

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

    /* 模块通用样式 */
    section {
      padding: 70px 0;
    }

    .section-header {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 45px auto;
    }

    .section-tag {
      display: inline-block;
      font-size: 13px;
      font-weight: 700;
      color: var(--primary-teal);
      text-transform: uppercase;
      letter-spacing: 1px;
      background: #e6f7f5;
      padding: 4px 12px;
      border-radius: 20px;
      margin-bottom: 12px;
    }

    .section-title {
      font-size: 32px;
      color: var(--text-main);
      font-weight: 800;
      margin-bottom: 14px;
      line-height: 1.3;
    }

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

    /* 首屏 Hero (无任何图片) */
    .hero-section {
      background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
      color: #ffffff;
      padding: 90px 0 100px 0;
      position: relative;
      overflow: hidden;
    }

    .hero-section::before {
      content: "";
      position: absolute;
      top: -50px;
      right: -50px;
      width: 450px;
      height: 450px;
      background: radial-gradient(circle, rgba(0, 168, 150, 0.25) 0%, rgba(0,0,0,0) 70%);
      pointer-events: none;
    }

    .hero-inner {
      text-align: center;
      max-width: 900px;
      margin: 0 auto;
      position: relative;
      z-index: 2;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: rgba(255, 255, 255, 0.12);
      border: 1px solid rgba(255, 255, 255, 0.25);
      padding: 6px 16px;
      border-radius: 30px;
      font-size: 14px;
      margin-bottom: 24px;
    }

    .hero-title-h1 {
      font-size: 38px;
      font-weight: 800;
      line-height: 1.25;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
      color: #ffffff;
    }

    .hero-desc {
      font-size: 18px;
      color: #e2e8f0;
      margin-bottom: 36px;
      line-height: 1.6;
    }

    .hero-actions {
      display: flex;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 50px;
    }

    .btn-primary {
      background: #00c9a7;
      color: #0d2b35;
      padding: 14px 32px;
      border-radius: 8px;
      font-weight: 700;
      text-decoration: none;
      font-size: 16px;
      transition: all 0.3s;
      border: none;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }

    .btn-primary:hover {
      background: #ffffff;
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(0, 201, 167, 0.4);
    }

    .btn-outline {
      background: rgba(255, 255, 255, 0.08);
      color: #ffffff;
      border: 1px solid rgba(255, 255, 255, 0.3);
      padding: 14px 32px;
      border-radius: 8px;
      font-weight: 600;
      text-decoration: none;
      font-size: 16px;
      transition: all 0.3s;
    }

    .btn-outline:hover {
      background: rgba(255, 255, 255, 0.2);
      border-color: #ffffff;
    }

    /* 数字卡片 - 首屏底部渲染 */
    .hero-stats {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      background: rgba(255, 255, 255, 0.06);
      border: 1px solid rgba(255, 255, 255, 0.12);
      border-radius: 12px;
      padding: 24px;
      backdrop-filter: blur(5px);
    }

    .stat-item {
      text-align: center;
    }

    .stat-num {
      font-size: 30px;
      font-weight: 800;
      color: #00c9a7;
    }

    .stat-label {
      font-size: 13px;
      color: #cbd5e1;
    }

    /* 卡片网格定义 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 24px;
    }

    .feature-card {
      background: var(--bg-card);
      border: 1px solid var(--border-light);
      border-radius: var(--radius);
      padding: 28px;
      transition: all 0.3s ease;
      box-shadow: var(--shadow-sm);
    }

    .feature-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
      border-color: var(--primary-teal);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: 10px;
      background: #e6f7f5;
      color: var(--primary-teal);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 20px;
      margin-bottom: 18px;
    }

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

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

    /* 场景矩阵 */
    .scenario-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
      gap: 20px;
    }

    .scenario-card {
      background: #ffffff;
      border-left: 4px solid var(--primary-teal);
      padding: 22px;
      border-radius: 0 8px 8px 0;
      box-shadow: 0 2px 6px rgba(0,0,0,0.04);
      border-top: 1px solid #edf2f7;
      border-right: 1px solid #edf2f7;
      border-bottom: 1px solid #edf2f7;
      transition: all 0.2s;
    }

    .scenario-card:hover {
      background: #f0fdfa;
      transform: translateX(4px);
    }

    .scenario-card h3 {
      font-size: 17px;
      color: var(--primary-dark);
      margin-bottom: 6px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .scenario-card p {
      font-size: 13.5px;
      color: var(--text-muted);
    }

    /* 标签云模型列表 */
    .model-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
    }

    .model-tag {
      background: #ffffff;
      border: 1px solid var(--border-light);
      padding: 8px 16px;
      border-radius: 20px;
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
      box-shadow: 0 2px 4px rgba(0,0,0,0.02);
      transition: all 0.2s;
    }

    .model-tag:hover {
      background: var(--primary-teal);
      color: #ffffff;
      border-color: var(--primary-teal);
    }

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

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 650px;
    }

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

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

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

    .highlight-col {
      background: #f0fdfa;
      font-weight: 700;
      color: var(--primary-dark);
    }

    .rating-banner {
      background: linear-gradient(135deg, #028090, #00a896);
      color: #fff;
      border-radius: var(--radius);
      padding: 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 24px;
      flex-wrap: wrap;
      gap: 16px;
    }

    .rating-score {
      font-size: 36px;
      font-weight: 900;
      color: #ffe600;
    }

    /* 案例中心展示 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 24px;
    }

    .case-card {
      background: #fff;
      border-radius: 10px;
      overflow: hidden;
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
    }

    .case-card-body {
      padding: 20px;
    }

    /* 流程时间线 */
    .timeline {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 20px;
      position: relative;
    }

    .step-item {
      background: #fff;
      padding: 24px;
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      position: relative;
    }

    .step-num {
      width: 32px;
      height: 32px;
      background: var(--primary-teal);
      color: #fff;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      margin-bottom: 12px;
    }

    /* 评论卡片 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
      gap: 20px;
    }

    .testimonial-card {
      background: #fff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow-sm);
    }

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

    .avatar-placeholder {
      width: 40px;
      height: 40px;
      background: #e2e8f0;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--primary-dark);
    }

    /* FAQ 折叠面板 */
    .faq-container {
      max-width: 860px;
      margin: 0 auto;
    }

    .faq-item {
      background: #fff;
      border: 1px solid var(--border-light);
      border-radius: 8px;
      margin-bottom: 12px;
      overflow: hidden;
    }

    .faq-question {
      width: 100%;
      padding: 18px 24px;
      text-align: left;
      background: none;
      border: none;
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-answer {
      padding: 0 24px 18px 24px;
      font-size: 14px;
      color: var(--text-muted);
      display: none;
      line-height: 1.7;
    }

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

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

    /* 表单与联系区 */
    .contact-wrapper {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: 12px;
      padding: 40px;
      box-shadow: var(--shadow-lg);
    }

    .form-group {
      margin-bottom: 18px;
    }

    .form-group label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 6px;
      color: var(--text-main);
    }

    .form-control {
      width: 100%;
      padding: 12px;
      border: 1px solid var(--border-light);
      border-radius: 6px;
      font-size: 14px;
      outline: none;
      transition: border 0.2s;
    }

    .form-control:focus {
      border-color: var(--primary-teal);
    }

    .contact-info-list {
      list-style: none;
      margin-top: 20px;
    }

    .contact-info-list li {
      margin-bottom: 14px;
      font-size: 15px;
      display: flex;
      align-items: center;
      gap: 10px;
    }

    /* 友情链接与底部 */
    .footer-section {
      background: #0d2b35;
      color: #94a3b8;
      padding: 60px 0 30px 0;
      font-size: 14px;
    }

    .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: 18px;
    }

    .footer-links {
      list-style: none;
    }

    .footer-links li {
      margin-bottom: 8px;
    }

    .footer-links a {
      color: #94a3b8;
      text-decoration: none;
      transition: color 0.2s;
    }

    .footer-links a:hover {
      color: #00c9a7;
    }

    .friend-links-box {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
      margin-bottom: 20px;
      display: flex;
      flex-wrap: wrap;
      gap: 15px;
      align-items: center;
    }

    .friend-links-box a {
      color: #cbd5e1;
      text-decoration: none;
    }

    .friend-links-box a:hover {
      color: #00c9a7;
    }

    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
      text-align: center;
      color: #64748b;
      font-size: 13px;
    }

    /* 浮动客服 */
    .floating-kefu {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      background: var(--primary-teal);
      color: #fff;
      width: 54px;
      height: 54px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 16px rgba(0,0,0,0.2);
      cursor: pointer;
      text-decoration: none;
      font-weight: 700;
      font-size: 13px;
      text-align: center;
    }

    /* 响应式适配 */
    @media (max-width: 992px) {
      .contact-wrapper {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .hero-stats {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .mobile-menu-btn {
        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-light);
        box-shadow: var(--shadow-lg);
      }
      .nav-links.active {
        display: flex;
      }
      .hero-title-h1 {
        font-size: 28px;
      }
      .section-title {
        font-size: 24px;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }