:root {
      --bg-main: #0c0814;
      --bg-card: #161026;
      --bg-card-hover: #1f1635;
      --border-color: rgba(236, 72, 153, 0.25);
      --border-glow: rgba(168, 85, 247, 0.4);
      --primary: #ec4899;
      --secondary: #a855f7;
      --accent: #06b6d4;
      --text-main: #f8fafc;
      --text-muted: #94a3b8;
      --text-dim: #cbd5e1;
      --gradient-brand: linear-gradient(135deg, #ec4899 0%, #a855f7 50%, #6366f1 100%);
      --container-width: 1200px;
    }

    * {
      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-main);
      color: var(--text-main);
    }

    body {
      background: radial-gradient(circle at 50% 0%, #2a1145 0%, #0c0814 70%);
      line-height: 1.6;
      overflow-x: hidden;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: color 0.3s ease;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

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

    /* 顶部导航 */
    header.site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(12, 8, 20, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-color);
    }

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

    .brand-box {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 1.25rem;
      font-weight: 700;
      letter-spacing: 0.5px;
    }

    .brand-box .ai-page-logo {
      height: 36px;
      width: auto;
    }

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

    .nav-links a {
      padding: 8px 14px;
      font-size: 0.92rem;
      color: var(--text-dim);
      border-radius: 6px;
      transition: all 0.25s ease;
    }

    .nav-links a:hover {
      color: #fff;
      background: rgba(236, 72, 153, 0.15);
    }

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 22px;
      font-size: 0.92rem;
      font-weight: 600;
      border-radius: 8px;
      cursor: pointer;
      border: none;
      transition: all 0.3s ease;
    }

    .btn-primary {
      background: var(--gradient-brand);
      color: #fff;
      box-shadow: 0 0 16px rgba(236, 72, 153, 0.4);
    }

    .btn-primary:hover {
      box-shadow: 0 0 24px rgba(236, 72, 153, 0.7);
      transform: translateY(-2px);
    }

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

    .btn-outline:hover {
      background: rgba(236, 72, 153, 0.2);
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      color: #fff;
      font-size: 1.5rem;
      cursor: pointer;
    }

    /* 首屏 Hero (无图片) */
    .hero-section {
      padding: 80px 0 60px;
      text-align: center;
      position: relative;
    }

    .hero-badge {
      display: inline-block;
      padding: 6px 16px;
      border-radius: 20px;
      background: rgba(236, 72, 153, 0.12);
      border: 1px solid rgba(236, 72, 153, 0.4);
      color: #f472b6;
      font-size: 0.85rem;
      margin-bottom: 20px;
      letter-spacing: 1px;
    }

    .hero-title {
      font-size: 2.8rem;
      font-weight: 800;
      line-height: 1.25;
      margin-bottom: 20px;
      background: linear-gradient(135deg, #ffffff 30%, #f472b6 70%, #c084fc 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-desc {
      max-width: 780px;
      margin: 0 auto 36px;
      font-size: 1.1rem;
      color: var(--text-dim);
      line-height: 1.8;
    }

    .hero-btns {
      display: flex;
      justify-content: center;
      gap: 18px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-top: 20px;
    }

    .stat-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 12px;
      padding: 24px;
      transition: all 0.3s ease;
    }

    .stat-card:hover {
      border-color: var(--primary);
      transform: translateY(-4px);
    }

    .stat-num {
      font-size: 2.2rem;
      font-weight: 800;
      color: #ec4899;
      margin-bottom: 4px;
    }

    .stat-label {
      font-size: 0.9rem;
      color: var(--text-muted);
    }

    /* 通用章节样式 */
    section {
      padding: 70px 0;
      border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }

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

    .section-subtitle {
      color: var(--primary);
      font-size: 0.85rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1.5px;
      margin-bottom: 8px;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: #fff;
    }

    .section-desc {
      color: var(--text-muted);
      max-width: 640px;
      margin: 12px auto 0;
      font-size: 0.95rem;
    }

    /* 栅格与卡片 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
      align-items: center;
    }

    .card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 14px;
      padding: 28px;
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
    }

    .card:hover {
      background: var(--bg-card-hover);
      border-color: var(--secondary);
      transform: translateY(-4px);
      box-shadow: 0 10px 24px rgba(168, 85, 247, 0.15);
    }

    .card-icon {
      width: 44px;
      height: 44px;
      border-radius: 8px;
      background: rgba(236, 72, 153, 0.15);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      margin-bottom: 18px;
      font-size: 1.25rem;
    }

    .card h3 {
      font-size: 1.2rem;
      margin-bottom: 12px;
      color: #fff;
    }

    .card p {
      color: var(--text-dim);
      font-size: 0.92rem;
      line-height: 1.6;
    }

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

    .step-box {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 12px;
      padding: 24px;
      position: relative;
    }

    .step-badge {
      font-size: 0.8rem;
      color: var(--accent);
      font-weight: 700;
      margin-bottom: 8px;
    }

    .step-title {
      font-size: 1.1rem;
      margin-bottom: 8px;
      color: #fff;
    }

    .step-text {
      font-size: 0.88rem;
      color: var(--text-muted);
    }

    /* 对比表格 */
    .table-container {
      overflow-x: auto;
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 14px;
    }

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

    .compare-table th, .compare-table td {
      padding: 18px 20px;
      border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    }

    .compare-table th {
      background: rgba(236, 72, 153, 0.1);
      color: #fff;
      font-size: 0.95rem;
    }

    .compare-table tr:hover td {
      background: rgba(255, 255, 255, 0.02);
    }

    .highlight-col {
      color: #f472b6;
      font-weight: 600;
      background: rgba(236, 72, 153, 0.05);
    }

    /* 评分卡片 */
    .score-banner {
      background: linear-gradient(135deg, rgba(236, 72, 153, 0.2), rgba(168, 85, 247, 0.2));
      border: 1px solid var(--primary);
      border-radius: 14px;
      padding: 24px 32px;
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 16px;
    }

    .score-info {
      display: flex;
      align-items: center;
      gap: 20px;
    }

    .score-num {
      font-size: 3rem;
      font-weight: 900;
      color: #f472b6;
      line-height: 1;
    }

    /* 标签云与多模型生态 */
    .tag-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-tag {
      background: rgba(255, 255, 255, 0.06);
      border: 1px solid rgba(255, 255, 255, 0.1);
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 0.85rem;
      color: var(--text-dim);
      transition: all 0.25s ease;
    }

    .model-tag:hover {
      border-color: var(--primary);
      color: #fff;
      background: rgba(236, 72, 153, 0.2);
    }

    /* 案例中心 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .case-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 12px;
      overflow: hidden;
    }

    .case-img-wrap {
      width: 100%;
      height: 200px;
      overflow: hidden;
      background: #000;
    }

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

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

    .case-content {
      padding: 20px;
    }

    .case-content h4 {
      font-size: 1.1rem;
      color: #fff;
      margin-bottom: 8px;
    }

    .case-content p {
      font-size: 0.88rem;
      color: var(--text-muted);
    }

    /* 用户评论 */
    .reviews-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .review-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 12px;
      padding: 24px;
      position: relative;
    }

    .review-meta {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 14px;
    }

    .review-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--gradient-brand);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: #fff;
    }

    .review-author {
      font-size: 0.95rem;
      color: #fff;
      font-weight: 600;
    }

    .review-role {
      font-size: 0.8rem;
      color: var(--accent);
    }

    .review-body {
      font-size: 0.9rem;
      color: var(--text-dim);
      line-height: 1.6;
    }

    /* FAQ 手风琴 */
    .faq-list {
      max-width: 860px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .faq-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 10px;
      overflow: hidden;
    }

    .faq-header {
      padding: 18px 24px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: #fff;
    }

    .faq-header:hover {
      background: rgba(236, 72, 153, 0.08);
    }

    .faq-arrow {
      transition: transform 0.3s ease;
      color: var(--primary);
    }

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

    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.35s ease;
      padding: 0 24px;
      color: var(--text-muted);
      font-size: 0.92rem;
      line-height: 1.7;
    }

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

    /* 表单区域 */
    .form-box {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 14px;
      padding: 36px;
    }

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

    .form-label {
      display: block;
      font-size: 0.9rem;
      margin-bottom: 6px;
      color: var(--text-dim);
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      background: rgba(12, 8, 20, 0.7);
      border: 1px solid rgba(255, 255, 255, 0.15);
      border-radius: 8px;
      color: #fff;
      font-size: 0.95rem;
      transition: border-color 0.25s ease;
    }

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

    /* 文章列表与外链展示 */
    .article-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
      margin-top: 16px;
    }

    .article-item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 12px 18px;
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: 8px;
      font-size: 0.92rem;
    }

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

    /* 友情链接与页脚 */
    footer.site-footer {
      background: #08050e;
      border-top: 1px solid var(--border-color);
      padding: 50px 0 24px;
      margin-top: auto;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 32px;
      margin-bottom: 40px;
    }

    .footer-col h5 {
      font-size: 1rem;
      color: #fff;
      margin-bottom: 16px;
    }

    .footer-col p, .footer-col li {
      font-size: 0.88rem;
      color: var(--text-muted);
      line-height: 1.8;
      list-style: none;
    }

    .footer-qr {
      width: 110px;
      height: 110px;
      padding: 4px;
      background: #fff;
      border-radius: 6px;
      margin-top: 10px;
    }

    .footer-bottom {
      text-align: center;
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      padding-top: 24px;
      font-size: 0.85rem;
      color: var(--text-muted);
    }

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      justify-content: center;
      margin-bottom: 16px;
    }

    .friend-links a {
      color: var(--text-muted);
      font-size: 0.85rem;
    }

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

    /* 悬浮客服 */
    .float-kefu {
      position: fixed;
      right: 20px;
      bottom: 40px;
      z-index: 999;
      background: var(--gradient-brand);
      border-radius: 50px;
      padding: 10px 18px;
      color: #fff;
      font-size: 0.88rem;
      font-weight: 600;
      box-shadow: 0 4px 16px rgba(236, 72, 153, 0.5);
      display: flex;
      align-items: center;
      gap: 8px;
      cursor: pointer;
    }

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

    @media (max-width: 768px) {
      .hero-title {
        font-size: 2rem;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #0c0814;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
      }
      .nav-links.active {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .grid-3, .step-grid, .case-grid, .reviews-grid, .stats-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }