:root {
      --brand-red: #d32f2f;
      --brand-red-dark: #b71c1c;
      --brand-red-light: #ffebee;
      --brand-red-hover: #ff5252;
      --brand-orange: #ff6f00;
      --text-main: #1f2429;
      --text-muted: #57606a;
      --text-light: #8c959f;
      --bg-page: #fcfaf8;
      --bg-card: #ffffff;
      --bg-alt: #fdf6f4;
      --border-color: #f1dfdc;
      --border-focus: #e57373;
      --shadow-sm: 0 2px 8px rgba(183, 28, 28, 0.05);
      --shadow-md: 0 8px 24px rgba(183, 28, 28, 0.08);
      --shadow-lg: 0 16px 36px rgba(183, 28, 28, 0.12);
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 16px;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    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: 1.6;
      -webkit-font-smoothing: antialiased;
    }

    .main-container {
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 顶部导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.96);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

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

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

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

    .brand-text {
      font-size: 20px;
      font-weight: 800;
      color: var(--brand-red-dark);
      letter-spacing: -0.5px;
    }

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

    .nav-links li a {
      text-decoration: none;
      color: var(--text-main);
      font-weight: 500;
      font-size: 14px;
      padding: 8px 12px;
      border-radius: var(--radius-sm);
      transition: all 0.2s ease;
      display: inline-block;
    }

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

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

    .btn-nav-primary {
      background: linear-gradient(135deg, var(--brand-red), var(--brand-red-dark));
      color: #fff !important;
      padding: 9px 18px;
      border-radius: 50px;
      text-decoration: none;
      font-size: 14px;
      font-weight: 600;
      box-shadow: 0 4px 12px rgba(211, 47, 47, 0.25);
      transition: all 0.25s ease;
      white-space: nowrap;
    }

    .btn-nav-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 16px rgba(211, 47, 47, 0.35);
    }

    .mobile-menu-btn {
      display: none;
      background: transparent;
      border: 1px solid var(--border-color);
      padding: 6px 10px;
      border-radius: var(--radius-sm);
      cursor: pointer;
      color: var(--text-main);
    }

    /* 首屏纯CSS与排版 */
    .hero-section {
      background: radial-gradient(circle at 80% 20%, rgba(255, 235, 238, 0.8) 0%, rgba(252, 250, 248, 0.95) 70%);
      padding: 70px 0 60px;
      position: relative;
      border-bottom: 1px solid var(--border-color);
    }

    .hero-wrap {
      display: grid;
      grid-template-columns: 1.15fr 0.85fr;
      gap: 40px;
      align-items: center;
    }

    .hero-content .badge-pill {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background-color: var(--brand-red-light);
      color: var(--brand-red-dark);
      padding: 6px 16px;
      border-radius: 50px;
      font-size: 13px;
      font-weight: 600;
      margin-bottom: 20px;
      border: 1px solid rgba(211, 47, 47, 0.2);
    }

    .hero-content h1 {
      font-size: 2.3rem;
      font-weight: 900;
      line-height: 1.25;
      color: #1a0f0f;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-content .lead-desc {
      font-size: 16px;
      color: var(--text-muted);
      margin-bottom: 30px;
      line-height: 1.7;
    }

    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 16px;
      margin-bottom: 32px;
    }

    .btn-official-hero {
      background: linear-gradient(135deg, #d32f2f, #b71c1c);
      color: #ffffff !important;
      padding: 14px 34px;
      border-radius: 50px;
      font-size: 16px;
      font-weight: 700;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      box-shadow: 0 8px 20px rgba(183, 28, 28, 0.3);
      transition: all 0.25s ease;
      border: 1px solid rgba(255, 255, 255, 0.3);
    }

    .btn-official-hero:hover {
      background: linear-gradient(135deg, #b71c1c, #8e0000);
      transform: translateY(-3px);
      box-shadow: 0 12px 28px rgba(183, 28, 28, 0.4);
    }

    .btn-secondary-hero {
      background-color: #ffffff;
      color: var(--brand-red-dark) !important;
      padding: 13px 26px;
      border-radius: 50px;
      font-size: 15px;
      font-weight: 600;
      text-decoration: none;
      border: 1px solid var(--border-color);
      transition: all 0.2s ease;
      box-shadow: var(--shadow-sm);
    }

    .btn-secondary-hero:hover {
      background-color: var(--brand-red-light);
      border-color: var(--brand-red);
    }

    .hero-features-list {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      font-size: 13px;
      color: var(--text-muted);
    }

    .hero-features-list span {
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }

    .hero-features-list span::before {
      content: "✓";
      color: var(--brand-red);
      font-weight: bold;
    }

    /* 首屏右侧纯CSS科技展牌 */
    .hero-tech-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 30px;
      box-shadow: var(--shadow-md);
      position: relative;
    }

    .tech-card-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-bottom: 1px dashed var(--border-color);
      padding-bottom: 15px;
      margin-bottom: 20px;
    }

    .tech-card-title {
      font-size: 16px;
      font-weight: 700;
      color: var(--brand-red-dark);
    }

    .model-tags-flow {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-bottom: 24px;
    }

    .model-badge {
      font-size: 12px;
      padding: 4px 10px;
      background: var(--bg-alt);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      color: var(--text-main);
      font-weight: 500;
    }

    .hero-stat-row {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
      background: var(--bg-alt);
      padding: 16px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
    }

    .stat-item-inner .stat-num {
      font-size: 24px;
      font-weight: 800;
      color: var(--brand-red);
      line-height: 1.1;
    }

    .stat-item-inner .stat-label {
      font-size: 12px;
      color: var(--text-muted);
      margin-top: 4px;
    }

    /* 区域统一标题 */
    .section-wrap {
      padding: 60px 0;
      border-bottom: 1px solid rgba(241, 223, 220, 0.6);
    }

    .section-header-block {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 44px;
    }

    .section-tag {
      color: var(--brand-red);
      font-size: 13px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      margin-bottom: 8px;
      display: inline-block;
    }

    .section-title {
      font-size: 1.85rem;
      font-weight: 800;
      color: #1a0f0f;
      margin-bottom: 14px;
    }

    .section-subtitle {
      font-size: 15px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* 矩阵网格通用 */
    .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;
    }

    /* 通用卡片 */
    .content-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
      transition: all 0.25s ease;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
    }

    .content-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: var(--border-focus);
    }

    .card-icon-box {
      width: 46px;
      height: 46px;
      border-radius: 10px;
      background-color: var(--brand-red-light);
      color: var(--brand-red);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 18px;
      margin-bottom: 16px;
    }

    .card-title {
      font-size: 17px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }

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

    /* 素材图展示区域 */
    .media-card-showcase {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
      margin-top: 30px;
    }

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

    .media-item-box .img-holder {
      aspect-ratio: 16/9;
      background-color: #f2e9e8;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .media-item-box .img-holder.square-holder {
      aspect-ratio: 1/1;
    }

    .media-item-box img {
      width: 100%;
      height: 100%;
      object-fit: contain;
      display: block;
    }

    .media-item-body {
      padding: 16px;
    }

    .media-item-title {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 6px;
    }

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

    /* 对比评测表格与卡片 */
    .evaluation-summary-box {
      background: linear-gradient(135deg, #fff5f5, #ffffff);
      border: 2px solid var(--brand-red);
      border-radius: var(--radius-lg);
      padding: 28px;
      margin-bottom: 30px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 20px;
    }

    .eval-score-wrap {
      display: flex;
      align-items: baseline;
      gap: 12px;
    }

    .eval-score-num {
      font-size: 3.2rem;
      font-weight: 900;
      color: var(--brand-red-dark);
      line-height: 1;
    }

    .eval-score-max {
      font-size: 16px;
      color: var(--text-muted);
    }

    .eval-stars {
      color: #ff9800;
      font-size: 20px;
      letter-spacing: 2px;
    }

    .eval-highlight-text {
      max-width: 600px;
      font-size: 14px;
      color: var(--text-muted);
    }

    .table-responsive-wrapper {
      width: 100%;
      overflow-x: auto;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      background: #ffffff;
      box-shadow: var(--shadow-sm);
    }

    .comparison-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 680px;
    }

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

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

    .comparison-table td.col-feature {
      font-weight: 600;
      color: var(--text-main);
    }

    .comparison-table td.col-brand {
      background-color: rgba(255, 235, 238, 0.4);
      font-weight: 700;
      color: var(--brand-red-dark);
    }

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

    .step-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 22px;
      position: relative;
    }

    .step-order {
      font-size: 28px;
      font-weight: 900;
      color: var(--brand-red);
      opacity: 0.25;
      position: absolute;
      top: 14px;
      right: 16px;
    }

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

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

    /* 常见问题面板 */
    .faq-container {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      overflow: hidden;
      transition: all 0.2s ease;
    }

    .faq-item.active {
      border-color: var(--brand-red);
      box-shadow: var(--shadow-sm);
    }

    .faq-question {
      padding: 16px 20px;
      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-question::after {
      content: "+";
      font-size: 18px;
      color: var(--brand-red);
      font-weight: bold;
      transition: transform 0.2s ease;
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: var(--bg-alt);
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      padding: 0 20px;
    }

    .faq-item.active .faq-answer {
      max-height: 300px;
      padding: 14px 20px 18px;
    }

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

    .testi-content {
      font-size: 14px;
      color: var(--text-muted);
      font-style: italic;
      margin-bottom: 16px;
      line-height: 1.6;
    }

    .testi-author-info {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px dashed var(--border-color);
      padding-top: 12px;
    }

    .author-initial {
      width: 36px;
      height: 36px;
      border-radius: 50%;
      background: var(--brand-red-light);
      color: var(--brand-red-dark);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 14px;
    }

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

    .author-meta .author-role {
      font-size: 12px;
      color: var(--text-light);
    }

    /* 表单与联络布局 */
    .contact-block-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 36px;
      align-items: flex-start;
    }

    .form-wrapper {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 30px;
      box-shadow: var(--shadow-md);
    }

    .form-group {
      margin-bottom: 16px;
    }

    .form-label {
      display: block;
      font-size: 13px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 6px;
    }

    .form-control {
      width: 100%;
      padding: 11px 14px;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 14px;
      color: var(--text-main);
      background-color: #fff;
      outline: none;
      transition: border-color 0.2s;
    }

    .form-control:focus {
      border-color: var(--brand-red);
    }

    textarea.form-control {
      resize: vertical;
      min-height: 90px;
    }

    .btn-submit-form {
      width: 100%;
      padding: 13px;
      background: linear-gradient(135deg, var(--brand-red), var(--brand-red-dark));
      color: #ffffff;
      border: none;
      border-radius: var(--radius-sm);
      font-size: 15px;
      font-weight: 700;
      cursor: pointer;
      transition: all 0.2s ease;
      box-shadow: 0 4px 12px rgba(211, 47, 47, 0.25);
    }

    .btn-submit-form:hover {
      opacity: 0.95;
      transform: translateY(-1px);
    }

    .contact-info-panel {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 30px;
      box-shadow: var(--shadow-sm);
    }

    .contact-items-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 16px;
      margin-bottom: 24px;
    }

    .contact-items-list li {
      display: flex;
      align-items: center;
      font-size: 14px;
      color: var(--text-muted);
      gap: 10px;
    }

    .contact-items-list strong {
      color: var(--text-main);
      min-width: 90px;
    }

    .qrcode-showcase {
      display: flex;
      align-items: center;
      gap: 20px;
      background: var(--bg-alt);
      padding: 16px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
    }

    .qrcode-box {
      width: 100px;
      height: 100px;
      background: #ffffff;
      padding: 4px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--border-color);
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .qrcode-box img {
      max-width: 100%;
      max-height: 100%;
      display: block;
      object-fit: contain;
    }

    /* 资讯文章列表 */
    .article-links-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
      margin-top: 20px;
    }

    .article-item-link {
      display: block;
      padding: 14px 18px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      text-decoration: none;
      color: var(--text-main);
      font-size: 14px;
      font-weight: 600;
      transition: all 0.2s ease;
    }

    .article-item-link:hover {
      border-color: var(--brand-red);
      color: var(--brand-red-dark);
      background-color: var(--brand-red-light);
    }

    /* 友情链接与版权收尾 */
    .site-footer {
      background-color: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 44px 0 24px;
      color: var(--text-muted);
    }

    .footer-top-grid {
      display: grid;
      grid-template-columns: 1.5fr 2.5fr;
      gap: 40px;
      margin-bottom: 30px;
    }

    .friend-links-area {
      font-size: 13px;
    }

    .friend-links-area h4 {
      font-size: 14px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }

    .friend-links-list {
      display: flex;
      flex-wrap: wrap;
      gap: 14px;
    }

    .friend-links-list a {
      color: var(--text-muted);
      text-decoration: none;
      transition: color 0.2s;
    }

    .friend-links-list a:hover {
      color: var(--brand-red);
    }

    .footer-bottom-bar {
      border-top: 1px solid var(--border-color);
      padding-top: 20px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 12px;
      font-size: 13px;
    }

    .footer-bottom-bar a {
      color: var(--text-muted);
      text-decoration: none;
    }

    .footer-bottom-bar a:hover {
      color: var(--brand-red);
    }

    /* 浮动客服 */
    .floating-widget {
      position: fixed;
      right: 20px;
      bottom: 40px;
      z-index: 99;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--brand-red);
      color: #fff;
      display: flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      box-shadow: 0 4px 14px rgba(211, 47, 47, 0.35);
      font-size: 13px;
      font-weight: 700;
      cursor: pointer;
      border: none;
    }

    .float-btn:hover {
      background: var(--brand-red-dark);
    }

    /* 响应式断点 */
    @media (max-width: 992px) {
      .hero-wrap {
        grid-template-columns: 1fr;
      }
      .grid-3, .media-card-showcase {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .step-chain {
        grid-template-columns: repeat(2, 1fr);
      }
      .contact-block-grid {
        grid-template-columns: 1fr;
      }
      .footer-top-grid {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 768px) {
      .mobile-menu-btn {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 16px 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.show {
        display: flex;
      }
      .nav-links li {
        width: 100%;
      }
      .nav-links li a {
        display: block;
        padding: 10px 14px;
      }
      .hero-content h1 {
        font-size: 1.8rem;
      }
      .grid-3, .grid-4, .grid-2, .media-card-showcase, .step-chain, .article-links-grid {
        grid-template-columns: 1fr;
      }
      .evaluation-summary-box {
        flex-direction: column;
        align-items: flex-start;
      }
      .footer-bottom-bar {
        flex-direction: column;
        text-align: center;
      }
    }