:root {
      --primary: #4f46e5;
      --primary-light: #6366f1;
      --accent: #ec4899;
      --accent-warm: #f59e0b;
      --cyan-bright: #06b6d4;
      --bg-page: #f8fafc;
      --bg-surface: #ffffff;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-sub: #64748b;
      --border-color: #e2e8f0;
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
      --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.05);
      --shadow-md: 0 10px 25px -5px rgba(79, 70, 229, 0.08), 0 8px 10px -6px rgba(15, 23, 42, 0.04);
      --shadow-hover: 0 20px 30px -10px rgba(79, 70, 229, 0.18);
      --container-width: 1200px;
      --transition: all 0.28s cubic-bezier(0.4, 0, 0.2, 1);
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }

    html {
      scroll-behavior: smooth;
    }

    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;
      position: relative;
      overflow-x: hidden;
      background-image: 
        radial-gradient(circle at 10% 20%, rgba(99, 102, 241, 0.05) 0%, transparent 40%),
        radial-gradient(circle at 90% 60%, rgba(236, 72, 153, 0.04) 0%, transparent 40%),
        radial-gradient(circle at 50% 90%, rgba(6, 182, 212, 0.04) 0%, transparent 50%);
      background-attachment: fixed;
    }

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

    .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: 1000;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: 0 2px 10px rgba(0, 0, 0, 0.03);
    }

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

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

    .brand-wrap .ai-page-logo {
      height: 40px;
      width: auto;
      display: block;
      object-fit: contain;
    }

    .brand-title {
      font-size: 20px;
      font-weight: 700;
      color: var(--text-main);
      letter-spacing: -0.02em;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .brand-badge {
      font-size: 11px;
      font-weight: 600;
      padding: 2px 8px;
      border-radius: 99px;
      background: linear-gradient(135deg, rgba(79, 70, 229, 0.1), rgba(236, 72, 153, 0.1));
      color: var(--primary);
      border: 1px solid rgba(99, 102, 241, 0.2);
    }

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

    .nav-links li a {
      padding: 8px 14px;
      font-size: 14px;
      font-weight: 500;
      color: var(--text-muted);
      border-radius: var(--radius-sm);
      display: block;
      white-space: nowrap;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--primary);
      background-color: rgba(79, 70, 229, 0.06);
    }

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      padding: 10px 22px;
      font-size: 14px;
      font-weight: 600;
      border-radius: 99px;
      cursor: pointer;
      border: none;
      outline: none;
      transition: var(--transition);
      white-space: nowrap;
      text-decoration: none;
    }

    .btn-primary {
      background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 50%, #ec4899 100%);
      color: #ffffff;
      box-shadow: 0 4px 15px rgba(99, 102, 241, 0.35);
    }

    .btn-primary:hover {
      box-shadow: 0 8px 25px rgba(236, 72, 153, 0.45);
      transform: translateY(-2px);
      color: #ffffff;
    }

    .btn-outline {
      background: #ffffff;
      color: var(--text-main);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

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

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

    /* 首屏 Hero 区域 (无图片，纯视觉与科技排版) */
    .hero-section {
      padding: 80px 0 60px;
      position: relative;
    }

    .hero-wrapper {
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
    }

    .hero-tag {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 16px;
      border-radius: 99px;
      background: linear-gradient(90deg, rgba(79, 70, 229, 0.08), rgba(236, 72, 153, 0.08));
      border: 1px solid rgba(79, 70, 229, 0.2);
      font-size: 13px;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 24px;
    }

    .hero-title {
      font-size: 46px;
      line-height: 1.25;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 20px;
      letter-spacing: -0.02em;
    }

    .hero-desc {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 820px;
      line-height: 1.7;
      margin-bottom: 36px;
    }

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

    .btn-hero-major {
      font-size: 16px;
      padding: 14px 34px;
      box-shadow: 0 10px 25px rgba(79, 70, 229, 0.4);
    }

    .model-chip-cloud {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 10px;
      max-width: 960px;
      margin-bottom: 20px;
    }

    .model-chip {
      background: #ffffff;
      border: 1px solid var(--border-color);
      padding: 6px 14px;
      border-radius: 99px;
      font-size: 12px;
      font-weight: 600;
      color: var(--text-muted);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }

    .model-chip:hover {
      border-color: var(--primary);
      color: var(--primary);
      transform: translateY(-2px);
      box-shadow: 0 4px 12px rgba(79, 70, 229, 0.15);
    }

    .model-chip-dot {
      width: 6px;
      height: 6px;
      border-radius: 50%;
      background: #10b981;
    }

    /* 指标看板 */
    .metrics-bar {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 30px;
      box-shadow: var(--shadow-md);
      margin-top: 20px;
      width: 100%;
    }

    .metric-item {
      text-align: center;
      border-right: 1px solid var(--border-color);
      padding: 0 10px;
    }

    .metric-item:last-child {
      border-right: none;
    }

    .metric-num {
      font-size: 32px;
      font-weight: 800;
      color: var(--text-main);
      background: linear-gradient(135deg, #4f46e5, #ec4899);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 6px;
      line-height: 1.2;
    }

    .metric-label {
      font-size: 13px;
      color: var(--text-sub);
      font-weight: 500;
    }

    /* 通用区块排版 */
    .section-spacing {
      padding: 70px 0;
      border-top: 1px solid rgba(226, 232, 240, 0.6);
    }

    .section-head {
      text-align: center;
      margin-bottom: 48px;
    }

    .section-subtitle {
      font-size: 12px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.1em;
      color: var(--primary);
      margin-bottom: 8px;
      display: inline-block;
    }

    .section-title {
      font-size: 32px;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 12px;
      letter-spacing: -0.01em;
    }

    .section-description {
      font-size: 15px;
      color: var(--text-muted);
      max-width: 680px;
      margin: 0 auto;
    }

    /* 网格卡片系统 */
    .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: 32px;
    }

    .feature-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      position: relative;
    }

    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(99, 102, 241, 0.4);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: 12px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: linear-gradient(135deg, rgba(79, 70, 229, 0.1), rgba(236, 72, 153, 0.1));
      color: var(--primary);
      margin-bottom: 18px;
    }

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

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

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

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

    .step-badge {
      width: 32px;
      height: 32px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      color: #ffffff;
      font-size: 13px;
      font-weight: 700;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 16px;
    }

    .step-title {
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--text-main);
    }

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

    /* 对比评测表格 */
    .comparison-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-md);
    }

    .rating-banner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      background: linear-gradient(135deg, #eef2ff, #fdf2f8);
      border: 1px solid rgba(99, 102, 241, 0.2);
      border-radius: var(--radius-md);
      padding: 20px 28px;
      margin-bottom: 28px;
      gap: 16px;
    }

    .rating-score {
      font-size: 34px;
      font-weight: 800;
      color: var(--primary);
    }

    .stars {
      color: #f59e0b;
      font-size: 18px;
      letter-spacing: 2px;
    }

    .table-container {
      width: 100%;
      overflow-x: auto;
    }

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

    .eval-table th, .eval-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
      font-size: 14px;
    }

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

    .eval-table td.highlight {
      background: rgba(79, 70, 229, 0.03);
      font-weight: 600;
      color: var(--primary);
    }

    .badge-win {
      display: inline-block;
      padding: 3px 10px;
      border-radius: 99px;
      background: #dcfce7;
      color: #15803d;
      font-size: 12px;
      font-weight: 600;
    }

    /* 案例展示区（含图片） */
    .case-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }

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

    .case-img-box {
      width: 100%;
      aspect-ratio: 16 / 9;
      overflow: hidden;
      background: #e2e8f0;
    }

    .case-img-box.square {
      aspect-ratio: 1 / 1;
    }

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

    .case-card:hover .case-img-box img {
      transform: scale(1.04);
    }

    .case-info {
      padding: 20px;
      flex-grow: 1;
      display: flex;
      flex-direction: column;
    }

    .case-tag {
      font-size: 12px;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 8px;
    }

    .case-title {
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--text-main);
    }

    .case-desc {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.5;
    }

    /* 宣传图画廊 */
    .banner-gallery {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
      margin-top: 30px;
    }

    .banner-gallery-item {
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .banner-gallery-item img {
      width: 100%;
      height: auto;
      display: block;
    }

    /* 客户评价板块 */
    .testimonial-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .user-avatar-circle {
      width: 42px;
      height: 42px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary-light), var(--accent));
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 15px;
    }

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

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

    /* 折叠面板 FAQ */
    .faq-container {
      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-md);
      overflow: hidden;
      transition: var(--transition);
    }

    .faq-item:hover {
      border-color: rgba(99, 102, 241, 0.4);
    }

    .faq-question {
      padding: 18px 24px;
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
    }

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

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

    .faq-answer {
      display: none;
      padding: 0 24px 20px;
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.7;
      border-top: 1px solid #f1f5f9;
      padding-top: 16px;
    }

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

    /* 需求匹配与表单 */
    .contact-wrapper {
      display: grid;
      grid-template-columns: 1fr 1.3fr;
      gap: 40px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 40px;
      box-shadow: var(--shadow-md);
    }

    .contact-info-side {
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .info-list {
      display: flex;
      flex-direction: column;
      gap: 16px;
      margin: 24px 0;
    }

    .info-row {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 14px;
      color: var(--text-muted);
    }

    .qr-box {
      background: #f8fafc;
      padding: 16px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      display: inline-flex;
      flex-direction: column;
      align-items: center;
      width: fit-content;
    }

    .qr-box img {
      width: 130px;
      height: 130px;
      object-fit: cover;
      border-radius: var(--radius-sm);
    }

    .qr-label {
      font-size: 12px;
      color: var(--text-sub);
      margin-top: 8px;
      font-weight: 600;
    }

    .form-box {
      display: flex;
      flex-direction: column;
      gap: 18px;
    }

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

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

    .form-input, .form-select, .form-textarea {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 14px;
      color: var(--text-main);
      background: #ffffff;
      transition: var(--transition);
      outline: none;
      font-family: inherit;
    }

    .form-input:focus, .form-select:focus, .form-textarea:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
    }

    .form-textarea {
      resize: vertical;
      min-height: 110px;
    }

    /* 文章列表 */
    .article-list {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 16px;
      margin-top: 24px;
    }

    .article-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 18px;
      transition: var(--transition);
    }

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

    .article-link {
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .article-link:hover {
      color: var(--primary);
    }

    /* 页脚 */
    .site-footer {
      background: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 60px 0 24px;
      margin-top: 60px;
      color: var(--text-main);
    }

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

    .footer-desc {
      font-size: 13px;
      color: var(--text-muted);
      margin-top: 14px;
      line-height: 1.6;
      max-width: 320px;
    }

    .footer-col-title {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 16px;
    }

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

    .footer-links li a {
      font-size: 13px;
      color: var(--text-muted);
    }

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

    .friend-links-box {
      border-top: 1px solid var(--border-color);
      padding-top: 24px;
      margin-bottom: 24px;
      font-size: 13px;
      color: var(--text-sub);
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 14px;
    }

    .friend-links-box a {
      color: var(--text-muted);
      background: #f1f5f9;
      padding: 4px 10px;
      border-radius: var(--radius-sm);
      font-size: 12px;
    }

    .friend-links-box a:hover {
      color: var(--primary);
      background: rgba(79, 70, 229, 0.08);
    }

    .footer-bottom {
      border-top: 1px solid var(--border-color);
      padding-top: 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 12px;
      color: var(--text-sub);
      flex-wrap: wrap;
      gap: 12px;
    }

    /* 悬浮工具栏 */
    .floating-bar {
      position: fixed;
      right: 20px;
      bottom: 40px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      z-index: 999;
    }

    .float-btn {
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: #ffffff;
      border: 1px solid var(--border-color);
      box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--text-main);
      cursor: pointer;
      transition: var(--transition);
      position: relative;
    }

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

    .float-btn-qr {
      position: absolute;
      right: 56px;
      bottom: 0;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 12px;
      box-shadow: var(--shadow-md);
      display: none;
      flex-direction: column;
      align-items: center;
      width: 140px;
    }

    .float-btn-qr img {
      width: 116px;
      height: 116px;
    }

    .float-btn:hover .float-btn-qr {
      display: flex;
    }

    /* 响应式断点 */
    @media (max-width: 992px) {
      .header-inner {
        position: relative;
      }
      .mobile-menu-toggle {
        display: block;
      }
      .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 74px;
        left: 0;
        right: 0;
        background: #ffffff;
        border-bottom: 1px solid var(--border-color);
        padding: 16px 24px;
        box-shadow: var(--shadow-md);
      }
      .nav-links.show {
        display: flex;
      }
      .nav-links li {
        width: 100%;
      }
      .nav-links li a {
        padding: 10px 0;
      }
      .metrics-bar {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
      }
      .metric-item:nth-child(2) {
        border-right: none;
      }
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .step-list {
        grid-template-columns: repeat(2, 1fr);
      }
      .contact-wrapper {
        grid-template-columns: 1fr;
      }
      .banner-gallery {
        grid-template-columns: 1fr;
      }
      .footer-content {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 640px) {
      .hero-title {
        font-size: 30px;
      }
      .hero-desc {
        font-size: 15px;
      }
      .metrics-bar {
        grid-template-columns: 1fr;
      }
      .metric-item {
        border-right: none;
        border-bottom: 1px solid var(--border-color);
        padding-bottom: 16px;
      }
      .metric-item:last-child {
        border-bottom: none;
        padding-bottom: 0;
      }
      .grid-3, .grid-4, .grid-2, .step-list {
        grid-template-columns: 1fr;
      }
      .footer-content {
        grid-template-columns: 1fr;
      }
      .floating-bar {
        right: 12px;
        bottom: 24px;
      }
    }