:root {
      --primary-yellow: #FFD000;
      --primary-yellow-light: #FFF4B8;
      --primary-yellow-dark: #E5BB00;
      --accent-black: #111827;
      --text-main: #1F2937;
      --text-muted: #4B5563;
      --text-light: #6B7280;
      --bg-light: #F9FAFB;
      --bg-card: #FFFFFF;
      --border-color: #E5E7EB;
      --border-accent: #FDE047;
      --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
      --shadow-md: 0 8px 24px rgba(17, 24, 39, 0.08);
      --shadow-hover: 0 14px 30px rgba(255, 208, 0, 0.25);
      --radius: 12px;
      --transition: all 0.25s ease;
    }

    * {
      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-light);
      color: var(--text-main);
      line-height: 1.6;
      overflow-x: hidden;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
    }

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

    /* 顶部导航 */
    header.site-header {
      background: #FFFFFF;
      border-bottom: 2px solid var(--primary-yellow);
      position: sticky;
      top: 0;
      z-index: 1000;
      box-shadow: var(--shadow-sm);
    }

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

    .brand-box {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
      color: var(--accent-black);
    }

    .brand-box .ai-page-logo {
      height: 42px;
      width: auto;
      display: block;
    }

    .brand-title {
      font-size: 1.25rem;
      font-weight: 800;
      letter-spacing: -0.5px;
      color: var(--accent-black);
    }

    .brand-tag {
      background: var(--primary-yellow);
      color: var(--accent-black);
      font-size: 0.75rem;
      padding: 2px 8px;
      border-radius: 4px;
      font-weight: 700;
    }

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

    .nav-links li a {
      text-decoration: none;
      color: var(--text-main);
      font-size: 0.95rem;
      font-weight: 600;
      padding: 8px 14px;
      border-radius: 6px;
      transition: var(--transition);
      display: inline-block;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--accent-black);
      background-color: var(--primary-yellow);
    }

    .nav-cta-btn {
      background-color: var(--accent-black);
      color: #FFFFFF !important;
      padding: 8px 18px !important;
      border-radius: 6px;
      margin-left: 8px;
    }

    .nav-cta-btn:hover {
      background-color: var(--primary-yellow-dark) !important;
      color: var(--accent-black) !important;
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: 1px solid var(--border-color);
      padding: 8px 12px;
      border-radius: 6px;
      cursor: pointer;
      font-size: 1.1rem;
      font-weight: bold;
    }

    /* 按钮通用 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1rem;
      padding: 12px 28px;
      border-radius: 8px;
      text-decoration: none;
      transition: var(--transition);
      cursor: pointer;
      border: 2px solid transparent;
      text-align: center;
    }

    .btn-primary {
      background: var(--primary-yellow);
      color: var(--accent-black);
      border-color: var(--primary-yellow-dark);
      box-shadow: 0 4px 12px rgba(255, 208, 0, 0.4);
    }

    .btn-primary:hover {
      background: #FFE033;
      transform: translateY(-2px);
      box-shadow: var(--shadow-hover);
    }

    .btn-dark {
      background: var(--accent-black);
      color: #FFFFFF;
    }

    .btn-dark:hover {
      background: #374151;
      transform: translateY(-2px);
    }

    .btn-outline {
      background: #FFFFFF;
      color: var(--accent-black);
      border-color: var(--accent-black);
    }

    .btn-outline:hover {
      background: var(--primary-yellow-light);
      border-color: var(--primary-yellow-dark);
    }

    .btn-large {
      padding: 16px 36px;
      font-size: 1.15rem;
    }

    /* 首屏 Hero（无图片） */
    .hero-section {
      background: linear-gradient(135deg, #FFFDE6 0%, #FFFFFF 60%, #FFF9D2 100%);
      border-bottom: 1px solid var(--border-color);
      padding: 70px 0 60px;
      position: relative;
    }

    .hero-content {
      text-align: center;
      max-width: 900px;
      margin: 0 auto;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: #FEF08A;
      color: #854D0E;
      border: 1px solid #FDE047;
      padding: 6px 16px;
      border-radius: 50px;
      font-size: 0.88rem;
      font-weight: 700;
      margin-bottom: 24px;
    }

    .hero-title {
      font-size: 2.75rem;
      line-height: 1.25;
      font-weight: 900;
      color: var(--accent-black);
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-title span {
      background: linear-gradient(180deg, transparent 65%, var(--primary-yellow) 65%);
      display: inline;
      padding: 0 4px;
    }

    .hero-desc {
      font-size: 1.15rem;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 32px;
      max-width: 800px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-cta-group {
      display: flex;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }

    .hero-features-strip {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
      gap: 16px;
      background: #FFFFFF;
      padding: 24px;
      border-radius: var(--radius);
      border: 1px solid var(--border-accent);
      box-shadow: var(--shadow-sm);
    }

    .feature-item {
      display: flex;
      align-items: flex-start;
      gap: 12px;
      text-align: left;
    }

    .feature-icon-box {
      width: 40px;
      height: 40px;
      background: var(--primary-yellow-light);
      color: var(--accent-black);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 900;
      font-size: 1.1rem;
      flex-shrink: 0;
    }

    .feature-item h4 {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--accent-black);
      margin-bottom: 2px;
    }

    .feature-item p {
      font-size: 0.82rem;
      color: var(--text-light);
      line-height: 1.4;
    }

    /* 模块通用样式 */
    section {
      padding: 60px 0;
      position: relative;
    }

    .section-alt {
      background-color: #FFFFFF;
      border-top: 1px solid var(--border-color);
      border-bottom: 1px solid var(--border-color);
    }

    .section-header {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 48px;
    }

    .section-eyebrow {
      display: inline-block;
      font-size: 0.85rem;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: 1px;
      background: var(--primary-yellow);
      color: var(--accent-black);
      padding: 4px 12px;
      border-radius: 4px;
      margin-bottom: 12px;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 800;
      color: var(--accent-black);
      margin-bottom: 12px;
    }

    .section-subtitle {
      font-size: 1rem;
      color: var(--text-muted);
    }

    /* 网格与卡片 */
    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

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

    .card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      transition: var(--transition);
      box-shadow: var(--shadow-sm);
    }

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

    .card-highlight {
      border: 2px solid var(--primary-yellow);
      background: linear-gradient(180deg, #FFFFFC 0%, #FFFDF0 100%);
    }

    /* 场景卡片 */
    .scenario-card {
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      height: 100%;
    }

    .scenario-tag {
      display: inline-block;
      font-size: 0.75rem;
      font-weight: 700;
      background: #FEF9C3;
      color: #713F12;
      padding: 3px 8px;
      border-radius: 4px;
      margin-bottom: 12px;
    }

    .scenario-card h3 {
      font-size: 1.15rem;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--accent-black);
    }

    .scenario-card p {
      font-size: 0.9rem;
      color: var(--text-muted);
      line-height: 1.5;
      margin-bottom: 16px;
      flex-grow: 1;
    }

    .scenario-footer {
      border-top: 1px dashed var(--border-color);
      padding-top: 12px;
      font-size: 0.82rem;
      color: var(--text-light);
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    /* 模型矩阵徽章云 */
    .models-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-chip {
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      color: var(--accent-black);
      padding: 8px 16px;
      border-radius: 30px;
      font-size: 0.88rem;
      font-weight: 600;
      box-shadow: 0 1px 3px rgba(0,0,0,0.03);
      transition: var(--transition);
    }

    .model-chip:hover {
      background: var(--primary-yellow);
      border-color: var(--primary-yellow-dark);
      transform: scale(1.05);
    }

    /* 评测与对比表格 */
    .review-summary-card {
      background: var(--accent-black);
      color: #FFFFFF;
      border-radius: var(--radius);
      padding: 32px;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 32px;
      gap: 20px;
    }

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

    .score-number {
      font-size: 3.5rem;
      font-weight: 900;
      color: var(--primary-yellow);
      line-height: 1;
    }

    .score-meta h4 {
      font-size: 1.25rem;
      font-weight: 700;
      margin-bottom: 4px;
      color: #FFFFFF;
    }

    .score-stars {
      color: var(--primary-yellow);
      font-size: 1.2rem;
    }

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

    .review-badge-item {
      background: rgba(255, 255, 255, 0.1);
      border: 1px solid rgba(255, 255, 255, 0.2);
      padding: 8px 16px;
      border-radius: 8px;
      font-size: 0.85rem;
      color: #F3F4F6;
    }

    .comparison-table-wrapper {
      overflow-x: auto;
      background: #FFFFFF;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      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: 16px 20px;
      border-bottom: 1px solid var(--border-color);
      font-size: 0.95rem;
    }

    .comparison-table th {
      background: #F9FAFB;
      font-weight: 700;
      color: var(--accent-black);
    }

    .comparison-table th.col-highlight {
      background: var(--primary-yellow-light);
      color: var(--accent-black);
      border-left: 2px solid var(--primary-yellow);
      border-right: 2px solid var(--primary-yellow);
    }

    .comparison-table td.col-highlight {
      background: #FFFEF5;
      font-weight: 600;
      color: var(--accent-black);
      border-left: 2px solid var(--primary-yellow);
      border-right: 2px solid var(--primary-yellow);
    }

    .table-check {
      color: #10B981;
      font-weight: 900;
      font-size: 1.1rem;
    }

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

    .step-card {
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      text-align: center;
      position: relative;
    }

    .step-num {
      width: 44px;
      height: 44px;
      background: var(--primary-yellow);
      color: var(--accent-black);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.25rem;
      font-weight: 900;
      margin: 0 auto 16px;
    }

    .step-card h3 {
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 8px;
    }

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

    /* 图片展示区 */
    .media-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 20px;
    }

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

    .media-card .img-wrap {
      width: 100%;
      aspect-ratio: 16 / 9;
      background: #F3F4F6;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }

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

    .media-card img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: var(--transition);
    }

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

    .media-info {
      padding: 16px;
    }

    .media-info h4 {
      font-size: 1rem;
      font-weight: 700;
      margin-bottom: 4px;
      color: var(--accent-black);
    }

    .media-info p {
      font-size: 0.85rem;
      color: var(--text-light);
    }

    /* 客户评论卡片 */
    .review-card {
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .review-author {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid #F3F4F6;
      padding-top: 12px;
    }

    .avatar-placeholder {
      width: 40px;
      height: 40px;
      background: var(--primary-yellow);
      color: var(--accent-black);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 0.9rem;
    }

    .author-info h4 {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--accent-black);
    }

    .author-info p {
      font-size: 0.8rem;
      color: var(--text-light);
    }

    /* FAQ 折叠 */
    .faq-list {
      max-width: 880px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      overflow: hidden;
      transition: var(--transition);
    }

    .faq-question {
      padding: 18px 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 700;
      font-size: 1rem;
      color: var(--accent-black);
      cursor: pointer;
      background: #FFFFFF;
    }

    .faq-question:hover {
      background-color: var(--primary-yellow-light);
    }

    .faq-icon {
      font-size: 1.25rem;
      font-weight: bold;
      transition: transform 0.2s ease;
    }

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

    .faq-item.active .faq-answer {
      padding: 0 20px 18px 20px;
      max-height: 250px;
    }

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

    /* 文章与资讯 */
    .article-box {
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      margin-bottom: 24px;
    }

    .article-links-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 12px;
      margin-top: 16px;
    }

    .article-link-item {
      display: block;
      background: #F9FAFB;
      border: 1px solid var(--border-color);
      padding: 10px 14px;
      border-radius: 6px;
      text-decoration: none;
      color: var(--text-main);
      font-size: 0.88rem;
      font-weight: 600;
      transition: var(--transition);
    }

    .article-link-item:hover {
      background: var(--primary-yellow-light);
      border-color: var(--primary-yellow);
      color: var(--accent-black);
    }

    /* 表单与联系区 */
    .contact-wrapper {
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      gap: 32px;
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 36px;
      box-shadow: var(--shadow-sm);
    }

    .contact-info-col h3 {
      font-size: 1.5rem;
      font-weight: 800;
      margin-bottom: 16px;
      color: var(--accent-black);
    }

    .contact-info-col p {
      color: var(--text-muted);
      font-size: 0.95rem;
      margin-bottom: 24px;
    }

    .contact-meta-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
      margin-bottom: 24px;
    }

    .contact-meta-item {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 0.95rem;
      color: var(--text-main);
    }

    .contact-meta-label {
      font-weight: 700;
      color: var(--accent-black);
      min-width: 90px;
    }

    .qrcode-box {
      display: inline-block;
      border: 1px solid var(--border-color);
      padding: 12px;
      border-radius: 8px;
      background: #FAFAFA;
      text-align: center;
    }

    .qrcode-box img {
      width: 130px;
      height: 130px;
      display: block;
      margin: 0 auto 6px;
      object-fit: contain;
    }

    .qrcode-box span {
      font-size: 0.8rem;
      color: var(--text-muted);
      font-weight: 600;
    }

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

    .form-group label {
      display: block;
      font-size: 0.9rem;
      font-weight: 700;
      margin-bottom: 6px;
      color: var(--accent-black);
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-color);
      border-radius: 6px;
      font-size: 0.95rem;
      font-family: inherit;
      background: #FFFFFF;
      transition: var(--transition);
    }

    .form-control:focus {
      outline: none;
      border-color: var(--primary-yellow-dark);
      box-shadow: 0 0 0 3px rgba(255, 208, 0, 0.25);
    }

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

    /* 底部通用规范 */
    footer.site-footer {
      background: #111827;
      color: #E5E7EB;
      padding: 50px 0 24px;
      border-top: 4px solid var(--primary-yellow);
      margin-top: auto;
    }

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

    .footer-col h4 {
      color: #FFFFFF;
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 16px;
      position: relative;
      padding-bottom: 8px;
    }

    .footer-col h4::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 24px;
      height: 2px;
      background: var(--primary-yellow);
    }

    .footer-col p {
      font-size: 0.88rem;
      color: #9CA3AF;
      line-height: 1.6;
      margin-bottom: 12px;
    }

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

    .footer-links li a {
      color: #D1D5DB;
      text-decoration: none;
      font-size: 0.88rem;
      transition: var(--transition);
    }

    .footer-links li a:hover {
      color: var(--primary-yellow);
      padding-left: 4px;
    }

    .friend-links-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 8px 12px;
    }

    .friend-links-wrap a {
      color: #9CA3AF;
      font-size: 0.85rem;
      text-decoration: none;
      transition: var(--transition);
      background: rgba(255, 255, 255, 0.05);
      padding: 4px 10px;
      border-radius: 4px;
    }

    .friend-links-wrap a:hover {
      color: var(--primary-yellow);
      background: rgba(255, 255, 255, 0.1);
    }

    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.1);
      padding-top: 20px;
      display: flex;
      flex-wrap: wrap;
      justify-content: space-between;
      align-items: center;
      font-size: 0.82rem;
      color: #9CA3AF;
    }

    .footer-bottom a {
      color: #D1D5DB;
      text-decoration: none;
    }

    /* 悬浮客服 */
    .float-kefu {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 50px;
      height: 50px;
      background: var(--primary-yellow);
      color: var(--accent-black);
      border-radius: 50%;
      box-shadow: 0 4px 14px rgba(0,0,0,0.15);
      display: flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      font-weight: 800;
      font-size: 0.82rem;
      transition: var(--transition);
      border: 2px solid #FFFFFF;
      cursor: pointer;
    }

    .float-btn:hover {
      transform: scale(1.1);
      background: #FFE033;
    }

    .back-top {
      display: none;
      background: #FFFFFF;
      color: var(--accent-black);
    }

    /* 响应式媒体查询 */
    @media (max-width: 992px) {
      .hero-title {
        font-size: 2.2rem;
      }
      .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .steps-container {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .contact-wrapper {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 768px) {
      .mobile-menu-btn {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #FFFFFF;
        flex-direction: column;
        padding: 20px;
        border-bottom: 2px solid var(--primary-yellow);
        box-shadow: var(--shadow-md);
      }
      .nav-links.show {
        display: flex;
      }
      .nav-links li {
        width: 100%;
      }
      .nav-links li a {
        display: block;
        padding: 12px 16px;
      }
      .nav-cta-btn {
        margin-left: 0;
        margin-top: 8px;
        text-align: center;
      }
      .hero-title {
        font-size: 1.8rem;
      }
      .hero-desc {
        font-size: 1rem;
      }
      .grid-3,
      .grid-2 {
        grid-template-columns: 1fr;
      }
      .steps-container {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .review-summary-card {
        flex-direction: column;
        align-items: flex-start;
      }
      .section-title {
        font-size: 1.6rem;
      }
    }