:root {
      --primary: #0052d9;
      --primary-hover: #003cab;
      --primary-light: #e8f1ff;
      --primary-gradient: linear-gradient(135deg, #0052d9 0%, #165dff 100%);
      --accent: #ff7d00;
      --bg-main: #f5f8fc;
      --bg-card: #ffffff;
      --text-main: #1d2129;
      --text-regular: #4e5969;
      --text-secondary: #86909c;
      --border-color: #e5e6eb;
      --border-light: #f2f3f5;
      --shadow-sm: 0 2px 8px rgba(0, 82, 217, 0.06);
      --shadow-md: 0 6px 20px rgba(0, 82, 217, 0.08);
      --shadow-lg: 0 12px 32px rgba(0, 82, 217, 0.12);
      --radius: 12px;
      --radius-sm: 6px;
      --container-width: 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, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
      background-color: var(--bg-main);
      color: var(--text-main);
      line-height: 1.6;
      overflow-x: hidden;
    }

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

    /* 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);
      box-shadow: var(--shadow-sm);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 70px;
    }

    .brand-box {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
    }

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

    .brand-title {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 0.5px;
    }

    .nav-container {
      display: flex;
      align-items: center;
    }

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

    .nav-links a {
      color: var(--text-main);
      text-decoration: none;
      font-size: 0.92rem;
      font-weight: 500;
      padding: 8px 12px;
      border-radius: var(--radius-sm);
      transition: all 0.25s ease;
      white-space: nowrap;
    }

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

    .nav-actions {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-left: 16px;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 9px 20px;
      font-size: 0.92rem;
      font-weight: 600;
      border-radius: var(--radius-sm);
      text-decoration: none;
      transition: all 0.25s ease;
      cursor: pointer;
      border: 1px solid transparent;
    }

    .btn-primary {
      background: var(--primary-gradient);
      color: #ffffff;
      box-shadow: 0 4px 12px rgba(0, 82, 217, 0.25);
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, #003cab 0%, #0d42c9 100%);
      transform: translateY(-2px);
      box-shadow: 0 6px 16px rgba(0, 82, 217, 0.35);
    }

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

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

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

    .menu-toggle span {
      width: 24px;
      height: 2px;
      background: var(--text-main);
      border-radius: 2px;
    }

    /* 区域通栏框架 */
    .section-wrap {
      padding: 70px 0;
      position: relative;
    }

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

    .section-badge {
      display: inline-block;
      padding: 4px 14px;
      background: var(--primary-light);
      color: var(--primary);
      font-size: 0.85rem;
      font-weight: 600;
      border-radius: 20px;
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
      line-height: 1.3;
    }

    .section-desc {
      font-size: 1rem;
      color: var(--text-regular);
      max-width: 680px;
      margin: 0 auto;
    }

    /* 首屏 Hero (严禁出现图片) */
    .hero-section {
      background: linear-gradient(180deg, #ffffff 0%, #eaf1fb 100%);
      padding: 80px 0 60px;
      border-bottom: 1px solid var(--border-color);
      position: relative;
      overflow: hidden;
    }

    .hero-content {
      text-align: center;
      max-width: 860px;
      margin: 0 auto;
      position: relative;
      z-index: 2;
    }

    .hero-badge-row {
      display: flex;
      justify-content: center;
      gap: 10px;
      flex-wrap: wrap;
      margin-bottom: 20px;
    }

    .hero-tag {
      background: #ffffff;
      color: var(--primary);
      border: 1px solid #bfdbfe;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.85rem;
      font-weight: 600;
      box-shadow: var(--shadow-sm);
    }

    .hero-title {
      font-size: 2.5rem;
      font-weight: 800;
      color: #0b1f44;
      line-height: 1.25;
      margin-bottom: 20px;
    }

    .hero-subtitle {
      font-size: 1.15rem;
      color: var(--text-regular);
      margin-bottom: 32px;
      line-height: 1.6;
    }

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

    .hero-btn-lg {
      padding: 14px 34px;
      font-size: 1.05rem;
      border-radius: 8px;
    }

    /* 首屏数据指标卡片 */
    .hero-metrics {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 18px;
      margin-top: 20px;
    }

    .metric-card {
      background: #ffffff;
      padding: 20px 16px;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: transform 0.25s ease;
    }

    .metric-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: #93c5fd;
    }

    .metric-number {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 4px;
    }

    .metric-label {
      font-size: 0.88rem;
      color: var(--text-regular);
      font-weight: 500;
    }

    /* 平台介绍与模型矩阵 */
    .models-bar {
      background: #ffffff;
      padding: 24px;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      margin-top: 32px;
      box-shadow: var(--shadow-sm);
    }

    .models-bar-title {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
      text-align: center;
    }

    .model-tags {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 8px;
    }

    .model-pill {
      background: var(--bg-main);
      border: 1px solid var(--border-color);
      color: #334155;
      font-size: 0.8rem;
      padding: 4px 10px;
      border-radius: 4px;
      font-weight: 500;
    }

    /* 服务网格卡片 */
    .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: 28px;
    }

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

    .card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
      border-color: #93c5fd;
    }

    .card-icon {
      width: 46px;
      height: 46px;
      border-radius: 8px;
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.2rem;
      margin-bottom: 16px;
    }

    .card-title {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }

    .card-desc {
      font-size: 0.92rem;
      color: var(--text-regular);
      line-height: 1.6;
      flex-grow: 1;
    }

    .card-meta {
      margin-top: 16px;
      padding-top: 12px;
      border-top: 1px solid var(--border-light);
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 0.85rem;
      color: var(--primary);
      font-weight: 600;
    }

    /* 流程步骤 */
    .step-timeline {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

    .step-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px 20px;
      position: relative;
      box-shadow: var(--shadow-sm);
    }

    .step-badge {
      width: 36px;
      height: 36px;
      background: var(--primary-gradient);
      color: #ffffff;
      font-weight: 700;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 14px;
    }

    .step-title {
      font-size: 1.05rem;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--text-main);
    }

    .step-desc {
      font-size: 0.88rem;
      color: var(--text-regular);
      line-height: 1.5;
    }

    /* 对比评测表格与卡片 */
    .evaluation-box {
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      padding: 32px;
      box-shadow: var(--shadow-sm);
    }

    .eval-highlight {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: linear-gradient(135deg, #f0f7ff 0%, #e0edff 100%);
      padding: 20px 24px;
      border-radius: var(--radius-sm);
      border: 1px solid #bfdbfe;
      margin-bottom: 24px;
    }

    .eval-score-num {
      font-size: 2.2rem;
      font-weight: 800;
      color: var(--primary);
      margin-right: 8px;
    }

    .eval-stars {
      color: #ff9800;
      font-size: 1.2rem;
      letter-spacing: 2px;
    }

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

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.92rem;
    }

    .compare-table th,
    .compare-table td {
      padding: 14px 18px;
      border-bottom: 1px solid var(--border-color);
    }

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

    .compare-table tr:hover td {
      background: #f8fbff;
    }

    .col-highlight {
      background: #f0f7ff;
      font-weight: 600;
      color: var(--primary);
    }

    /* 案例展示区媒体样式 */
    .media-card {
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
    }

    .media-img-wrap {
      width: 100%;
      aspect-ratio: 16 / 9;
      background: #e2e8f0;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .media-img-wrap.square {
      aspect-ratio: 1 / 1;
    }

    .media-img-wrap img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: transform 0.3s ease;
    }

    .media-card:hover .media-img-wrap img {
      transform: scale(1.03);
    }

    .media-info {
      padding: 20px;
    }

    .media-tag {
      font-size: 0.78rem;
      color: var(--primary);
      font-weight: 600;
      background: var(--primary-light);
      padding: 2px 8px;
      border-radius: 4px;
      display: inline-block;
      margin-bottom: 8px;
    }

    /* 评论板块 */
    .review-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 22px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .review-text {
      font-size: 0.92rem;
      color: var(--text-regular);
      line-height: 1.6;
      margin-bottom: 16px;
      font-style: italic;
    }

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

    .user-avatar {
      width: 40px;
      height: 40px;
      border-radius: 50%;
      background: var(--primary-gradient);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 0.9rem;
    }

    .user-name {
      font-weight: 700;
      font-size: 0.9rem;
      color: var(--text-main);
    }

    .user-role {
      font-size: 0.78rem;
      color: var(--text-secondary);
    }

    /* 需求匹配与表单 */
    .form-wrapper {
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      padding: 36px;
      box-shadow: var(--shadow-sm);
    }

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

    .form-label {
      display: block;
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .form-input,
    .form-select,
    .form-textarea {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 0.92rem;
      background: #fcfdfe;
      color: var(--text-main);
      outline: none;
      transition: border-color 0.25s ease;
    }

    .form-input:focus,
    .form-select:focus,
    .form-textarea:focus {
      border-color: var(--primary);
      background: #ffffff;
      box-shadow: 0 0 0 3px rgba(0, 82, 217, 0.1);
    }

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

    /* FAQ 折叠 */
    .faq-container {
      display: flex;
      flex-direction: column;
      gap: 12px;
      max-width: 900px;
      margin: 0 auto;
    }

    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      overflow: hidden;
      transition: all 0.25s ease;
    }

    .faq-header {
      padding: 16px 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 600;
      color: var(--text-main);
      background: #ffffff;
    }

    .faq-header:hover {
      background: #f8fbff;
      color: var(--primary);
    }

    .faq-icon {
      font-size: 1.1rem;
      transition: transform 0.25s ease;
      color: var(--primary);
    }

    .faq-content {
      padding: 0 20px;
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: #fcfdfe;
      color: var(--text-regular);
      font-size: 0.92rem;
      line-height: 1.6;
    }

    .faq-item.active .faq-content {
      padding: 12px 20px 18px;
      max-height: 240px;
      border-top: 1px solid var(--border-light);
    }

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

    /* 文章列表 & 百科 */
    .article-list {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 18px;
    }

    .article-link-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      padding: 16px 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      text-decoration: none;
      color: var(--text-main);
      transition: all 0.25s ease;
    }

    .article-link-item:hover {
      border-color: var(--primary);
      background: var(--primary-light);
      color: var(--primary);
      transform: translateX(4px);
    }

    /* 联系我们与客服二维码 */
    .contact-box {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 32px;
      box-shadow: var(--shadow-sm);
    }

    .contact-details {
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .contact-item {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 0.95rem;
      color: var(--text-regular);
    }

    .contact-item strong {
      color: var(--text-main);
      min-width: 80px;
    }

    .qr-container {
      text-align: center;
      padding: 20px;
      background: #f8fafc;
      border-radius: var(--radius-sm);
      border: 1px solid var(--border-color);
      max-width: 220px;
      margin: 0 auto;
    }

    .qr-container img {
      width: 140px;
      height: 140px;
      object-fit: contain;
      margin-bottom: 8px;
      display: block;
      margin-left: auto;
      margin-right: auto;
    }

    /* 友情链接与通用尾部 */
    .links-block {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      padding: 20px 24px;
      margin-top: 32px;
    }

    .links-title {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }

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

    .links-flex a {
      color: var(--text-regular);
      text-decoration: none;
      font-size: 0.88rem;
      padding: 4px 10px;
      background: var(--bg-main);
      border-radius: 4px;
      border: 1px solid var(--border-light);
      transition: all 0.2s ease;
    }

    .links-flex a:hover {
      color: var(--primary);
      border-color: #93c5fd;
      background: var(--primary-light);
    }

    /* 页脚 */
    .site-footer {
      background: #0d1a30;
      color: #94a3b8;
      padding: 48px 0 24px;
      border-top: 1px solid #1e293b;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 32px;
      margin-bottom: 36px;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 1rem;
      margin-bottom: 16px;
      font-weight: 700;
    }

    .footer-col p {
      font-size: 0.88rem;
      line-height: 1.6;
      margin-bottom: 12px;
    }

    .footer-links-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .footer-links-list a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.88rem;
      transition: color 0.2s ease;
    }

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

    .footer-bottom {
      border-top: 1px solid #1e293b;
      padding-top: 20px;
      text-align: center;
      font-size: 0.82rem;
      color: #64748b;
    }

    /* 浮动入口 */
    .floating-service {
      position: fixed;
      right: 20px;
      bottom: 80px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
      transition: transform 0.2s ease;
      cursor: pointer;
      border: none;
    }

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

    /* 响应式媒体查询 */
    @media (max-width: 992px) {
      .hero-metrics {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3, .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .step-timeline {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .menu-toggle {
        display: flex;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 16px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.show {
        display: flex;
      }
      .hero-title {
        font-size: 1.85rem;
      }
      .section-title {
        font-size: 1.6rem;
      }
      .grid-3, .grid-4, .grid-2 {
        grid-template-columns: 1fr;
      }
      .step-timeline {
        grid-template-columns: 1fr;
      }
      .hero-metrics {
        grid-template-columns: 1fr;
      }
      .article-list {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }