:root {
      --primary: #6c2bd9;
      --primary-light: #8b5cf6;
      --primary-dark: #4c1d95;
      --primary-glow: rgba(108, 43, 217, 0.12);
      --accent: #ec4899;
      --bg-base: #f8f6fc;
      --bg-surface: #ffffff;
      --bg-soft: #f1ecf9;
      --text-main: #1f1d2b;
      --text-sub: #524d63;
      --text-muted: #8c859d;
      --border: #e6def2;
      --shadow-sm: 0 4px 12px rgba(108, 43, 217, 0.05);
      --shadow-md: 0 10px 30px rgba(108, 43, 217, 0.08);
      --shadow-lg: 0 20px 45px rgba(108, 43, 217, 0.14);
      --radius: 14px;
      --container-width: 1200px;
    }

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

    html {
      scroll-behavior: smooth;
      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);
    }

    body {
      background: radial-gradient(circle at 10% 10%, #f3ebfc 0%, #f8f6fc 40%),
                  radial-gradient(circle at 90% 90%, #f6e8f8 0%, #f8f6fc 50%);
      background-attachment: fixed;
      color: var(--text-main);
      line-height: 1.6;
      overflow-x: hidden;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: all 0.25s ease;
    }

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

    /* 顶部导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border);
    }

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

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

    .ai-page-logo {
      height: 40px;
      width: auto;
      object-fit: contain;
      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-sub);
      padding: 8px 12px;
      border-radius: 6px;
    }

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

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 22px;
      font-size: 14px;
      font-weight: 600;
      border-radius: 8px;
      cursor: pointer;
      transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
      border: 1px solid transparent;
      white-space: nowrap;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(108, 43, 217, 0.28);
    }

    .btn-primary:hover {
      box-shadow: 0 6px 20px rgba(108, 43, 217, 0.4);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: #ffffff;
      color: var(--primary);
      border: 1px solid var(--border);
    }

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

    .nav-toggle {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 6px;
    }

    .nav-toggle span {
      width: 22px;
      height: 2px;
      background: var(--text-main);
      border-radius: 2px;
    }

    /* Section 通用 */
    section {
      padding: 80px 0;
    }

    .section-head {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 50px;
    }

    .section-tag {
      display: inline-block;
      font-size: 12px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      color: var(--primary);
      background: var(--primary-glow);
      padding: 4px 14px;
      border-radius: 30px;
      margin-bottom: 12px;
    }

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

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

    /* 首屏 Hero */
    .hero-section {
      padding: 90px 0 70px;
      text-align: center;
      position: relative;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: #ffffff;
      border: 1px solid var(--border);
      padding: 6px 18px;
      border-radius: 40px;
      font-size: 13px;
      color: var(--primary-dark);
      font-weight: 600;
      margin-bottom: 24px;
      box-shadow: var(--shadow-sm);
    }

    .hero-title {
      font-size: 46px;
      font-weight: 900;
      color: #1a162b;
      line-height: 1.25;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-title span {
      color: var(--primary);
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-subtitle {
      font-size: 18px;
      color: var(--text-sub);
      max-width: 820px;
      margin: 0 auto 36px;
    }

    .hero-cta-group {
      display: flex;
      justify-content: center;
      gap: 16px;
      margin-bottom: 40px;
      flex-wrap: wrap;
    }

    .hero-features-strip {
      display: flex;
      justify-content: center;
      gap: 28px;
      flex-wrap: wrap;
      margin-top: 20px;
    }

    .strip-item {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 13px;
      font-weight: 500;
      color: var(--text-sub);
    }

    .strip-item svg {
      color: var(--primary);
    }

    /* 数据指标 */
    .stats-wrapper {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-top: 40px;
    }

    .stat-card {
      background: #ffffff;
      border: 1px solid var(--border);
      padding: 24px;
      border-radius: var(--radius);
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: transform 0.25s ease;
    }

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

    .stat-number {
      font-size: 36px;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.1;
      margin-bottom: 6px;
    }

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

    /* 服务卡片网格 */
    .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: 30px;
    }

    .service-card {
      background: #ffffff;
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 28px;
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
      box-shadow: var(--shadow-sm);
    }

    .service-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
      border-color: var(--primary-light);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: 12px;
      background: var(--primary-glow);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      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-sub);
      line-height: 1.6;
      flex-grow: 1;
    }

    /* 模型矩阵徽章云 */
    .model-tags-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 30px;
    }

    .model-pill {
      background: #ffffff;
      border: 1px solid var(--border);
      padding: 8px 16px;
      border-radius: 30px;
      font-size: 13px;
      font-weight: 600;
      color: var(--text-sub);
      box-shadow: var(--shadow-sm);
      transition: all 0.2s;
    }

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

    /* 标准流程时间线 */
    .process-timeline {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

    .process-step {
      background: #ffffff;
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 24px;
      position: relative;
      box-shadow: var(--shadow-sm);
    }

    .step-idx {
      font-size: 20px;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 12px;
    }

    /* 案例中心图文 */
    .case-card {
      background: #ffffff;
      border: 1px solid var(--border);
      border-radius: var(--radius);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
    }

    .case-img-holder {
      width: 100%;
      height: 200px;
      background: var(--bg-soft);
      overflow: hidden;
    }

    .case-img-holder img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: transform 0.4s ease;
    }

    .case-card:hover .case-img-holder img {
      transform: scale(1.05);
    }

    .case-body {
      padding: 24px;
      flex-grow: 1;
      display: flex;
      flex-direction: column;
    }

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

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

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

    .eval-table th {
      background: var(--bg-soft);
      font-weight: 700;
      color: var(--text-main);
    }

    .eval-highlight {
      background: rgba(108, 43, 217, 0.04);
      font-weight: 600;
      color: var(--primary-dark);
    }

    .badge-score {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: linear-gradient(135deg, #10b981 0%, #059669 100%);
      color: #ffffff;
      padding: 4px 10px;
      border-radius: 6px;
      font-size: 12px;
      font-weight: 700;
    }

    /* FAQ 折叠 */
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
    }

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

    .faq-question {
      width: 100%;
      padding: 18px 22px;
      text-align: left;
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      background: none;
      border: none;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }

    .faq-icon {
      font-size: 18px;
      transition: transform 0.25s ease;
      color: var(--primary);
    }

    .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;
      padding: 0 22px;
      font-size: 14px;
      color: var(--text-sub);
      background: #faf8fd;
      line-height: 1.6;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 14px 22px 18px;
      border-top: 1px solid var(--border);
    }

    /* 评论卡片 */
    .review-card {
      background: #ffffff;
      border: 1px solid var(--border);
      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-sub);
      margin-bottom: 16px;
      font-style: italic;
    }

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

    .reviewer-avatar {
      width: 38px;
      height: 38px;
      border-radius: 50%;
      background: var(--primary-glow);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 14px;
    }

    .reviewer-name {
      font-size: 14px;
      font-weight: 700;
      color: var(--text-main);
    }

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

    /* 表单区域 */
    .form-wrapper {
      background: #ffffff;
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 36px;
      box-shadow: var(--shadow-md);
    }

    .form-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
    }

    .form-group {
      display: flex;
      flex-direction: column;
      gap: 6px;
    }

    .form-group.full-width {
      grid-column: span 2;
    }

    .form-label {
      font-size: 13px;
      font-weight: 600;
      color: var(--text-main);
    }

    .form-control {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid var(--border);
      border-radius: 8px;
      font-size: 14px;
      color: var(--text-main);
      background: #fdfcff;
      outline: none;
      transition: border-color 0.2s;
    }

    .form-control:focus {
      border-color: var(--primary);
      background: #ffffff;
    }

    /* 资讯与友情链接 */
    .article-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .article-item a {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 14px 18px;
      background: #ffffff;
      border: 1px solid var(--border);
      border-radius: 8px;
      font-size: 14px;
      color: var(--text-sub);
    }

    .article-item a:hover {
      border-color: var(--primary);
      color: var(--primary);
      padding-left: 22px;
    }

    /* 页脚 */
    .site-footer {
      background: #191426;
      color: #b7b0cb;
      padding: 60px 0 30px;
      border-top: 1px solid #2d2642;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr 1.5fr;
      gap: 30px;
      margin-bottom: 40px;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 15px;
      font-weight: 700;
      margin-bottom: 16px;
    }

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
      font-size: 13px;
    }

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

    .qr-box {
      width: 110px;
      background: #ffffff;
      padding: 6px;
      border-radius: 8px;
      margin-top: 10px;
    }

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

    .footer-bottom {
      border-top: 1px solid #28213d;
      padding-top: 24px;
      text-align: center;
      font-size: 13px;
      color: #797191;
    }

    /* 悬浮客服 */
    .float-contact {
      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: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 16px rgba(108, 43, 217, 0.4);
      cursor: pointer;
      border: none;
      transition: transform 0.2s;
    }

    .float-btn:hover {
      transform: scale(1.1);
    }

    /* 响应式调整 */
    @media (max-width: 992px) {
      .grid-3, .grid-4, .stats-wrapper, .process-timeline {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-2 {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .hero-title {
        font-size: 36px;
      }
      .nav-links {
        display: none;
      }
      .nav-toggle {
        display: flex;
      }
      .nav-links.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        border-bottom: 1px solid var(--border);
        padding: 16px 24px;
        box-shadow: var(--shadow-md);
      }
    }

    @media (max-width: 600px) {
      .grid-3, .grid-4, .stats-wrapper, .process-timeline, .faq-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .form-grid {
        grid-template-columns: 1fr;
      }
      .form-group.full-width {
        grid-column: span 1;
      }
      .hero-title {
        font-size: 28px;
      }
      section {
        padding: 50px 0;
      }
    }