:root {
      --primary: #4f46e5;
      --primary-hover: #4338ca;
      --primary-light: #eef2ff;
      --secondary: #06b6d4;
      --accent: #f43f5e;
      --accent-gradient: linear-gradient(135deg, #4f46e5 0%, #06b6d4 50%, #f43f5e 100%);
      --bg-main: #f8fafc;
      --bg-card: #ffffff;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-light: #64748b;
      --border-color: #e2e8f0;
      --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
      --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.04);
      --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.03);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --radius-full: 9999px;
      --container-max: 1200px;
    }

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

    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-main);
      color: var(--text-main);
      line-height: 1.6;
    }

    body {
      overflow-x: hidden;
      background: radial-gradient(circle at 10% 10%, rgba(79, 70, 229, 0.04) 0%, transparent 40%),
                  radial-gradient(circle at 90% 90%, rgba(6, 182, 212, 0.05) 0%, transparent 40%),
                  var(--bg-main);
    }

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

    /* 顶部导航 */
    .header-nav {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-color);
      transition: all 0.3s ease;
    }

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

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

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

    .brand-title {
      font-size: 20px;
      font-weight: 700;
      color: var(--text-main);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .brand-tag {
      font-size: 11px;
      font-weight: 600;
      padding: 2px 8px;
      border-radius: var(--radius-full);
      background: var(--primary-light);
      color: var(--primary);
    }

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

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

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

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

    .btn-portal {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 9px 20px;
      font-size: 14px;
      font-weight: 600;
      color: #ffffff;
      background: var(--accent-gradient);
      border-radius: var(--radius-full);
      text-decoration: none;
      box-shadow: 0 4px 12px rgba(79, 70, 229, 0.25);
      transition: transform 0.2s, box-shadow 0.2s;
    }

    .btn-portal:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 16px rgba(79, 70, 229, 0.35);
    }

    .mobile-menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 22px;
      color: var(--text-main);
      cursor: pointer;
      padding: 6px;
    }

    /* 按钮通用 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      padding: 12px 28px;
      font-size: 15px;
      font-weight: 600;
      border-radius: var(--radius-full);
      text-decoration: none;
      cursor: pointer;
      transition: all 0.25s ease;
      border: 1px solid transparent;
    }

    .btn-primary {
      background: var(--accent-gradient);
      color: #ffffff;
      box-shadow: 0 8px 20px rgba(79, 70, 229, 0.28);
    }

    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 10px 24px rgba(79, 70, 229, 0.36);
    }

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

    .btn-outline:hover {
      background: var(--bg-main);
      border-color: var(--primary);
      color: var(--primary);
      transform: translateY(-2px);
    }

    /* 首屏 Hero - 无图片 pure CSS 亮彩微光 */
    .hero-section {
      padding: 70px 0 60px;
      position: relative;
      text-align: center;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 18px;
      background: rgba(79, 70, 229, 0.08);
      border: 1px solid rgba(79, 70, 229, 0.2);
      border-radius: var(--radius-full);
      font-size: 13px;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 24px;
    }

    .hero-badge-pulse {
      width: 8px;
      height: 8px;
      background: #10b981;
      border-radius: 50%;
      box-shadow: 0 0 0 4px rgba(16, 185, 129, 0.2);
      animation: pulseAnim 2s infinite;
    }

    @keyframes pulseAnim {
      0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4); }
      70% { box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
      100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
    }

    .hero-title {
      font-size: 42px;
      font-weight: 800;
      line-height: 1.25;
      color: var(--text-main);
      margin-bottom: 20px;
      letter-spacing: -1px;
    }

    .hero-subtitle {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 780px;
      margin: 0 auto 36px;
      line-height: 1.7;
    }

    .hero-cta-group {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 16px;
      margin-bottom: 50px;
      flex-wrap: wrap;
    }

    .hero-stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      max-width: 980px;
      margin: 0 auto;
    }

    .stat-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px 16px;
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s, box-shadow 0.2s;
    }

    .stat-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: rgba(79, 70, 229, 0.3);
    }

    .stat-value {
      font-size: 32px;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 6px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 2px;
    }

    .stat-label {
      font-size: 13px;
      color: var(--text-muted);
      font-weight: 500;
    }

    /* 区域通用规范 */
    .section-block {
      padding: 80px 0;
      position: relative;
    }

    .section-header {
      text-align: center;
      max-width: 720px;
      margin: 0 auto 50px;
    }

    .section-tag {
      display: inline-block;
      font-size: 12px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      color: var(--secondary);
      background: rgba(6, 182, 212, 0.1);
      padding: 4px 12px;
      border-radius: var(--radius-full);
      margin-bottom: 12px;
    }

    .section-title {
      font-size: 32px;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 14px;
      letter-spacing: -0.5px;
    }

    .section-desc {
      font-size: 15px;
      color: var(--text-muted);
      line-height: 1.7;
    }

    /* 模型矩阵徽章云 */
    .model-pills-wrap {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 10px;
      max-width: 1000px;
      margin: 30px auto 0;
    }

    .model-pill {
      background: #ffffff;
      border: 1px solid var(--border-color);
      padding: 8px 16px;
      border-radius: var(--radius-full);
      font-size: 13px;
      font-weight: 600;
      color: var(--text-main);
      box-shadow: var(--shadow-sm);
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: all 0.2s ease;
    }

    .model-pill:hover {
      border-color: var(--primary);
      color: var(--primary);
      transform: translateY(-2px);
    }

    .model-dot {
      width: 6px;
      height: 6px;
      border-radius: 50%;
      background: var(--secondary);
    }

    /* 场景卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

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

    .feature-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 28px 24px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
    }

    .feature-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(79, 70, 229, 0.3);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: var(--radius-sm);
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 22px;
      margin-bottom: 20px;
    }

    .feature-card h3 {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }

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

    .card-footer-tag {
      margin-top: 16px;
      padding-top: 14px;
      border-top: 1px solid var(--border-color);
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 12px;
      color: var(--text-light);
    }

    /* 流程与步骤 */
    .step-timeline {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 16px;
      position: relative;
    }

    .step-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px 18px;
      text-align: center;
      position: relative;
      box-shadow: var(--shadow-sm);
    }

    .step-num {
      width: 36px;
      height: 36px;
      line-height: 36px;
      border-radius: 50%;
      background: var(--accent-gradient);
      color: #ffffff;
      font-weight: 800;
      font-size: 14px;
      margin: 0 auto 16px;
    }

    .step-item h4 {
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 8px;
    }

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

    /* 对比评测表格与卡片 */
    .comparison-wrapper {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-md);
    }

    .score-banner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: linear-gradient(135deg, #eef2ff 0%, #e0e7ff 100%);
      padding: 20px 28px;
      border-radius: var(--radius-md);
      margin-bottom: 28px;
      border: 1px solid rgba(79, 70, 229, 0.2);
    }

    .score-left h4 {
      font-size: 20px;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 4px;
    }

    .score-left p {
      font-size: 14px;
      color: var(--text-muted);
    }

    .score-right {
      display: flex;
      align-items: baseline;
      gap: 8px;
    }

    .score-number {
      font-size: 40px;
      font-weight: 900;
      color: var(--primary);
      line-height: 1;
    }

    .score-total {
      font-size: 18px;
      color: var(--text-light);
      font-weight: 600;
    }

    .score-stars {
      color: #f59e0b;
      font-size: 20px;
      letter-spacing: 2px;
    }

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

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

    .custom-table th, .custom-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
      font-size: 14px;
    }

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

    .custom-table td.highlight {
      background: rgba(79, 70, 229, 0.03);
      color: var(--primary);
      font-weight: 600;
    }

    /* 案例展示区 */
    .media-gallery-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      margin-bottom: 24px;
    }

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

    .media-img-wrap {
      width: 100%;
      background: #f1f5f9;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
    }

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

    .media-img-wrap img:hover {
      transform: scale(1.02);
    }

    .media-info {
      padding: 18px 20px;
    }

    .media-info h4 {
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 6px;
    }

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

    .banner-trio {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
      margin-top: 24px;
    }

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

    /* 用户评论 */
    .testimonial-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .avatar-placeholder {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 15px;
    }

    .reviewer-info h4 {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
    }

    .reviewer-info p {
      font-size: 12px;
      color: var(--text-light);
    }

    .testimonial-body {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      font-style: normal;
    }

    .review-stars {
      color: #f59e0b;
      font-size: 14px;
      margin-top: 12px;
    }

    /* FAQ 折叠 */
    .faq-container {
      max-width: 860px;
      margin: 0 auto;
    }

    .faq-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      margin-bottom: 14px;
      overflow: hidden;
      transition: border-color 0.2s;
    }

    .faq-item:hover {
      border-color: rgba(79, 70, 229, 0.3);
    }

    .faq-question {
      padding: 20px 24px;
      width: 100%;
      text-align: left;
      background: none;
      border: none;
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-icon {
      font-size: 18px;
      color: var(--primary);
      transition: transform 0.25s ease;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: #fafafa;
    }

    .faq-answer-inner {
      padding: 0 24px 20px;
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.7;
    }

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

    .faq-item.active .faq-answer {
      max-height: 240px;
    }

    /* 表单与联系区 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1.1fr 0.9fr;
      gap: 32px;
      align-items: start;
    }

    .form-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-md);
    }

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

    .form-label {
      display: block;
      font-size: 14px;
      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: 14px;
      color: var(--text-main);
      background: #ffffff;
      outline: none;
      transition: border-color 0.2s;
      font-family: inherit;
    }

    .form-input:focus, .form-select:focus, .form-textarea:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
    }

    .contact-info-card {
      background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-sm);
    }

    .contact-channel-list {
      list-style: none;
      margin-bottom: 28px;
    }

    .contact-channel-item {
      display: flex;
      align-items: flex-start;
      gap: 14px;
      margin-bottom: 18px;
      font-size: 14px;
      color: var(--text-muted);
    }

    .contact-channel-icon {
      width: 32px;
      height: 32px;
      border-radius: 8px;
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      flex-shrink: 0;
      font-size: 14px;
      font-weight: 700;
    }

    .qr-container {
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 20px;
      background: #ffffff;
      border: 1px dashed var(--border-color);
      border-radius: var(--radius-md);
      text-align: center;
    }

    .qr-container img {
      max-width: 150px;
      height: auto;
      border-radius: 6px;
      margin-bottom: 10px;
    }

    .qr-container span {
      font-size: 13px;
      font-weight: 600;
      color: var(--text-main);
    }

    /* 行业资讯文章区 */
    .article-links-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 16px;
      margin-top: 20px;
    }

    .article-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 16px 20px;
      text-decoration: none;
      color: var(--text-main);
      font-size: 14px;
      font-weight: 500;
      display: flex;
      align-items: center;
      justify-content: space-between;
      box-shadow: var(--shadow-sm);
      transition: all 0.2s;
    }

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

    /* 页脚与友情链接 */
    .site-footer {
      background: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 60px 0 30px;
      color: var(--text-muted);
    }

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

    .footer-brand p {
      font-size: 14px;
      line-height: 1.7;
      margin-top: 14px;
      color: var(--text-muted);
    }

    .footer-col h5 {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 16px;
    }

    .footer-links {
      list-style: none;
    }

    .footer-links li {
      margin-bottom: 10px;
    }

    .footer-links a {
      font-size: 14px;
      color: var(--text-muted);
      text-decoration: none;
      transition: color 0.2s;
    }

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

    .friendly-links-section {
      padding: 20px 0;
      border-top: 1px solid var(--border-color);
      border-bottom: 1px solid var(--border-color);
      margin-bottom: 30px;
    }

    .friendly-links-title {
      font-size: 13px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }

    .friendly-links-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
    }

    .friendly-links-wrap a {
      font-size: 13px;
      color: var(--text-light);
      text-decoration: none;
      transition: color 0.2s;
    }

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

    .footer-bottom {
      text-align: center;
      font-size: 13px;
      color: var(--text-light);
    }

    /* 悬浮工具 */
    .floating-tools {
      position: fixed;
      right: 24px;
      bottom: 30px;
      z-index: 99;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #ffffff;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-md);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--text-main);
      cursor: pointer;
      text-decoration: none;
      font-size: 18px;
      transition: all 0.2s;
    }

    .float-btn:hover {
      background: var(--primary);
      color: #ffffff;
      transform: translateY(-3px);
    }

    /* 响应式适配 */
    @media (max-width: 1024px) {
      .hero-stats-grid { grid-template-columns: repeat(2, 1fr); }
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .step-timeline { grid-template-columns: repeat(3, 1fr); }
      .footer-top { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.active { display: flex; }
      .mobile-menu-toggle { display: block; }
      .hero-title { font-size: 28px; }
      .hero-subtitle { font-size: 15px; }
      .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
      .step-timeline { grid-template-columns: 1fr; }
      .media-gallery-grid { grid-template-columns: 1fr; }
      .banner-trio { grid-template-columns: 1fr; }
      .contact-grid { grid-template-columns: 1fr; }
      .footer-top { grid-template-columns: 1fr; }
      .article-links-grid { grid-template-columns: 1fr; }
    }