:root {
      --primary: #ff5e36;
      --primary-hover: #e04822;
      --accent-yellow: #ffc93c;
      --accent-blue: #0084ff;
      --accent-green: #00c897;
      --accent-purple: #7b2cbf;
      --text-main: #1f242d;
      --text-sub: #555d6e;
      --text-light: #7c8698;
      --bg-main: #faf9f6;
      --bg-card: #ffffff;
      --border-color: #24292f;
      --shadow-hard: 4px 4px 0px #24292f;
      --shadow-hard-hover: 6px 6px 0px #24292f;
      --radius-sm: 8px;
      --radius-md: 16px;
      --radius-lg: 24px;
    }

    * {
      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, sans-serif;
      background-color: var(--bg-main);
      color: var(--text-main);
      line-height: 1.6;
      overflow-x: hidden;
      background-image: radial-gradient(#e5e2db 1px, transparent 1px);
      background-size: 24px 24px;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: all 0.2s ease;
    }

    .container {
      width: 100%;
      max-width: 1240px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 顶部导航 */
    .header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.95);
      border-bottom: 3px solid var(--border-color);
      backdrop-filter: blur(8px);
    }

    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 76px;
    }

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

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

    .brand-title {
      font-size: 1.25rem;
      font-weight: 900;
      color: var(--text-main);
      letter-spacing: -0.5px;
    }

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

    .nav-links li {
      margin: 0 10px;
    }

    .nav-links a {
      font-weight: 700;
      font-size: 0.95rem;
      padding: 6px 10px;
      border-radius: var(--radius-sm);
      border: 2px solid transparent;
    }

    .nav-links a:hover {
      background: var(--accent-yellow);
      border-color: var(--border-color);
    }

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      padding: 10px 22px;
      border-radius: var(--radius-md);
      border: 3px solid var(--border-color);
      cursor: pointer;
      box-shadow: var(--shadow-hard);
      transition: transform 0.15s ease, box-shadow 0.15s ease;
      text-align: center;
    }

    .btn:hover {
      transform: translate(-2px, -2px);
      box-shadow: var(--shadow-hard-hover);
    }

    .btn:active {
      transform: translate(2px, 2px);
      box-shadow: 0 0 0 #000;
    }

    .btn-primary {
      background: var(--primary);
      color: #fff;
    }

    .btn-secondary {
      background: var(--accent-yellow);
      color: var(--text-main);
    }

    .btn-outline {
      background: #fff;
      color: var(--text-main);
    }

    .nav-toggle {
      display: none;
      background: #fff;
      border: 2px solid var(--border-color);
      padding: 8px 12px;
      font-weight: bold;
      border-radius: var(--radius-sm);
      box-shadow: 2px 2px 0 var(--border-color);
    }

    /* 首屏 Hero */
    .hero-section {
      padding: 80px 0 60px;
      position: relative;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1.2fr 0.8fr;
      gap: 40px;
      align-items: center;
    }

    .hero-tag-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-bottom: 20px;
    }

    .badge-doodle {
      display: inline-block;
      font-size: 0.85rem;
      font-weight: 800;
      padding: 6px 14px;
      border: 2px solid var(--border-color);
      border-radius: 20px;
      box-shadow: 2px 2px 0 var(--border-color);
      background: #fff;
    }

    .hero-h1 {
      font-size: 2.75rem;
      line-height: 1.2;
      font-weight: 900;
      margin-bottom: 20px;
      color: var(--text-main);
    }

    .hero-desc {
      font-size: 1.15rem;
      color: var(--text-sub);
      margin-bottom: 30px;
      line-height: 1.7;
    }

    .hero-action {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      margin-bottom: 40px;
    }

    .hero-feature-board {
      background: #ffffff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: 6px 6px 0 var(--border-color);
      position: relative;
    }

    .board-title {
      font-size: 1.2rem;
      font-weight: 800;
      margin-bottom: 16px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .board-list {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
    }

    .board-item {
      background: #f4f6fb;
      border: 2px solid var(--border-color);
      border-radius: var(--radius-sm);
      padding: 12px;
      font-size: 0.9rem;
      font-weight: 700;
      box-shadow: 2px 2px 0 var(--border-color);
    }

    /* 数据指标条 */
    .stat-section {
      padding: 20px 0 60px;
    }

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

    .stat-card {
      background: #fff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
      text-align: center;
      box-shadow: var(--shadow-hard);
    }

    .stat-num {
      font-size: 2.2rem;
      font-weight: 900;
      color: var(--primary);
      margin-bottom: 4px;
    }

    .stat-label {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--text-sub);
    }

    /* 通用章节 */
    .section-block {
      padding: 70px 0;
      position: relative;
    }

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

    .section-subtitle {
      display: inline-block;
      font-size: 0.9rem;
      font-weight: 800;
      text-transform: uppercase;
      background: var(--accent-yellow);
      padding: 4px 14px;
      border: 2px solid var(--border-color);
      border-radius: 20px;
      margin-bottom: 12px;
      box-shadow: 2px 2px 0 var(--border-color);
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 900;
      margin-bottom: 12px;
      color: var(--text-main);
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--text-sub);
    }

    /* 卡片通用网格 */
    .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;
    }

    .doodle-card {
      background: var(--bg-card);
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 26px;
      box-shadow: var(--shadow-hard);
      transition: all 0.2s ease;
      display: flex;
      flex-direction: column;
    }

    .doodle-card:hover {
      transform: translate(-3px, -3px);
      box-shadow: var(--shadow-hard-hover);
    }

    .card-icon-tag {
      font-size: 1.5rem;
      display: inline-block;
      margin-bottom: 14px;
      width: 48px;
      height: 48px;
      line-height: 44px;
      text-align: center;
      background: var(--accent-yellow);
      border: 2px solid var(--border-color);
      border-radius: 12px;
      box-shadow: 2px 2px 0 var(--border-color);
    }

    .card-title {
      font-size: 1.25rem;
      font-weight: 800;
      margin-bottom: 10px;
      color: var(--text-main);
    }

    .card-text {
      font-size: 0.95rem;
      color: var(--text-sub);
      line-height: 1.6;
      flex-grow: 1;
    }

    /* 平台介绍特别板块 */
    .intro-box {
      background: #fff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 40px;
      box-shadow: 8px 8px 0 var(--border-color);
      margin-bottom: 40px;
    }

    .tag-cloud-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 20px;
    }

    .tag-pill {
      background: #f1f3f9;
      border: 2px solid var(--border-color);
      padding: 6px 14px;
      font-size: 0.85rem;
      font-weight: 700;
      border-radius: 20px;
      box-shadow: 2px 2px 0 var(--border-color);
    }

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

    .step-num {
      width: 40px;
      height: 40px;
      background: var(--primary);
      color: #fff;
      font-weight: 900;
      border: 2px solid var(--border-color);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 16px;
      box-shadow: 2px 2px 0 var(--border-color);
    }

    /* 评测对比与评分 */
    .rating-banner {
      background: #fffae6;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      box-shadow: var(--shadow-hard);
      margin-bottom: 30px;
    }

    .rating-score {
      font-size: 2.8rem;
      font-weight: 900;
      color: var(--primary);
    }

    .table-container {
      width: 100%;
      overflow-x: auto;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-hard);
      background: #fff;
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 600px;
    }

    .compare-table th, .compare-table td {
      padding: 16px 20px;
      border-bottom: 2px solid #e5e5e5;
      border-right: 2px solid #e5e5e5;
    }

    .compare-table th {
      background: #f4f6fb;
      font-weight: 800;
      color: var(--text-main);
    }

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

    .compare-table td:last-child, .compare-table th:last-child {
      border-right: none;
    }

    .highlight-col {
      background: #fff9f0;
      font-weight: 700;
      color: var(--primary);
    }

    /* 案例展示 */
    .case-card {
      background: #fff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-hard);
    }

    .case-img-wrap {
      width: 100%;
      aspect-ratio: 16/9;
      background: #eee;
      border-bottom: 3px solid var(--border-color);
      overflow: hidden;
    }

    .case-img-wrap img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }

    .case-body {
      padding: 20px;
    }

    /* 评论卡片 */
    .review-user {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 16px;
      padding-top: 14px;
      border-top: 2px dashed #ddd;
    }

    .review-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      border: 2px solid var(--border-color);
      background: var(--accent-yellow);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 900;
    }

    /* FAQ折叠 */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 16px;
      max-width: 900px;
      margin: 0 auto;
    }

    .faq-item {
      background: #fff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-hard);
      overflow: hidden;
    }

    .faq-question {
      padding: 20px 24px;
      font-weight: 800;
      font-size: 1.1rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: #fff;
      user-select: none;
    }

    .faq-question::after {
      content: '+';
      font-size: 1.5rem;
      font-weight: 900;
      transition: transform 0.2s ease;
    }

    .faq-item.active .faq-question::after {
      content: '-';
    }

    .faq-answer {
      display: none;
      padding: 0 24px 20px;
      color: var(--text-sub);
      font-size: 0.95rem;
      line-height: 1.7;
    }

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

    /* 表单区域 */
    .form-container {
      background: #fff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: 8px 8px 0 var(--border-color);
    }

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

    .form-label {
      display: block;
      font-weight: 800;
      margin-bottom: 8px;
      font-size: 0.95rem;
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 2px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 1rem;
      background: #fdfdfd;
      box-shadow: 2px 2px 0 #ddd;
      outline: none;
    }

    .form-control:focus {
      border-color: var(--primary);
      box-shadow: 2px 2px 0 var(--border-color);
    }

    /* 文章列表 */
    .article-box {
      background: #fff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-hard);
      margin-bottom: 24px;
    }

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

    .article-link-item {
      padding: 8px 14px;
      background: #f0f4ff;
      border: 2px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-weight: 700;
      font-size: 0.9rem;
      box-shadow: 2px 2px 0 var(--border-color);
    }

    /* 友情链接与页脚 */
    .footer {
      background: #ffffff;
      border-top: 3px solid var(--border-color);
      padding: 60px 0 30px;
      color: var(--text-main);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-title {
      font-size: 1.1rem;
      font-weight: 900;
      margin-bottom: 16px;
      color: var(--text-main);
      display: inline-block;
      border-bottom: 2px solid var(--primary);
      padding-bottom: 4px;
    }

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
      font-weight: 600;
      font-size: 0.9rem;
    }

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

    .friend-links-area {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 10px;
    }

    .friend-links-area a {
      background: #f4f6fb;
      padding: 6px 12px;
      border: 2px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 0.85rem;
      font-weight: 700;
      color: var(--text-main);
    }

    .qr-box {
      width: 130px;
      padding: 6px;
      background: #fff;
      border: 2px solid var(--border-color);
      border-radius: var(--radius-sm);
      box-shadow: 3px 3px 0 var(--border-color);
    }

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

    .footer-bottom {
      text-align: center;
      padding-top: 30px;
      border-top: 2px dashed #ddd;
      font-size: 0.9rem;
      font-weight: 700;
      color: var(--text-light);
    }

    /* 浮动客服 */
    .float-kefu {
      position: fixed;
      right: 24px;
      bottom: 30px;
      z-index: 999;
      background: #fff;
      border: 3px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 12px 18px;
      box-shadow: 4px 4px 0 var(--border-color);
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 800;
      cursor: pointer;
    }

    .float-kefu:hover {
      background: var(--accent-yellow);
    }

    /* 响应式调整 */
    @media (max-width: 992px) {
      .hero-grid, .grid-3, .grid-4, .process-grid, .footer-grid, .grid-2 {
        grid-template-columns: 1fr;
      }
      .stat-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 76px;
        left: 0;
        width: 100%;
        background: #fff;
        flex-direction: column;
        padding: 20px;
        border-bottom: 3px solid var(--border-color);
        box-shadow: 0 8px 16px rgba(0,0,0,0.1);
      }
      .nav-links.active {
        display: flex;
      }
      .nav-links li {
        margin: 10px 0;
        width: 100%;
        text-align: center;
      }
      .nav-toggle {
        display: block;
      }
      .hero-h1 {
        font-size: 2.1rem;
      }
    }

    @media (max-width: 600px) {
      .stat-grid {
        grid-template-columns: 1fr;
      }
      .rating-banner {
        flex-direction: column;
        gap: 16px;
        text-align: center;
      }
    }