:root {
      --primary: #2563eb;
      --primary-dark: #1d4ed8;
      --primary-light: #eff6ff;
      --accent: #f59e0b;
      --accent-hover: #d97706;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-sub: #64748b;
      --bg-page: #f8fafc;
      --bg-surface: #ffffff;
      --bg-alt: #f1f5f9;
      --border-color: #e2e8f0;
      --border-focus: #93c5fd;
      --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, 0.05);
      --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.03);
      --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 16px;
      --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }

    * {
      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", "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;
      overflow-x: hidden;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: var(--transition);
    }

    ul, ol {
      list-style: none;
    }

    .container {
      width: 100%;
      max-width: 1200px;
      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, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
    }

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

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

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

    .brand-title {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--text-main);
      letter-spacing: -0.5px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 0;
    }

    .nav-link {
      display: inline-block;
      padding: 8px 14px;
      font-size: 0.938rem;
      font-weight: 500;
      color: var(--text-muted);
      border-radius: var(--radius-sm);
    }

    .nav-link:hover {
      color: var(--primary);
      background-color: var(--primary-light);
    }

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

    .btn-portal {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 9px 18px;
      font-size: 0.875rem;
      font-weight: 600;
      color: #ffffff;
      background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
      border-radius: 9999px;
      box-shadow: 0 2px 8px rgba(37, 99, 235, 0.35);
      white-space: nowrap;
    }

    .btn-portal:hover {
      background: linear-gradient(135deg, #1d4ed8 0%, #1e40af 100%);
      transform: translateY(-1px);
      box-shadow: 0 4px 12px rgba(37, 99, 235, 0.45);
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
      color: var(--text-main);
    }

    /* Hero 首屏 - 无任何图片 */
    .hero-section {
      background: linear-gradient(180deg, #f0f7ff 0%, #f8fafc 100%);
      padding: 64px 0 54px;
      border-bottom: 1px solid var(--border-color);
      position: relative;
    }

    .hero-content {
      text-align: center;
      max-width: 920px;
      margin: 0 auto;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background-color: #ffffff;
      border: 1px solid #bfdbfe;
      color: var(--primary);
      padding: 6px 16px;
      border-radius: 9999px;
      font-size: 0.875rem;
      font-weight: 600;
      margin-bottom: 20px;
      box-shadow: var(--shadow-sm);
    }

    .hero-badge-dot {
      width: 8px;
      height: 8px;
      background-color: #10b981;
      border-radius: 50%;
      display: inline-block;
    }

    .hero-title {
      font-size: 2.5rem;
      font-weight: 800;
      line-height: 1.25;
      color: var(--text-main);
      margin-bottom: 20px;
      letter-spacing: -0.02em;
    }

    .hero-desc {
      font-size: 1.125rem;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 36px;
      max-width: 820px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-cta-group {
      display: flex;
      justify-content: center;
      align-items: center;
      flex-wrap: wrap;
      gap: 16px;
      margin-bottom: 40px;
    }

    .btn-main-portal {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      font-size: 1.063rem;
      font-weight: 700;
      color: #ffffff;
      background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
      border-radius: 8px;
      box-shadow: 0 4px 14px rgba(37, 99, 235, 0.4);
    }

    .btn-main-portal:hover {
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(37, 99, 235, 0.45);
    }

    .btn-secondary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 28px;
      font-size: 1.063rem;
      font-weight: 600;
      color: var(--text-main);
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      box-shadow: var(--shadow-sm);
    }

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

    .hero-metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      margin-top: 10px;
    }

    .metric-card {
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 20px 16px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .metric-card:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow-md);
      border-color: var(--border-focus);
    }

    .metric-val {
      font-size: 1.875rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 4px;
    }

    .metric-label {
      font-size: 0.875rem;
      color: var(--text-muted);
      font-weight: 500;
    }

    /* 模块通用样式 */
    .section-wrap {
      padding: 72px 0;
      border-bottom: 1px solid var(--border-color);
    }

    .section-wrap.bg-light {
      background-color: #ffffff;
    }

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

    .section-tag {
      display: inline-block;
      font-size: 0.813rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      color: var(--primary);
      background-color: var(--primary-light);
      padding: 4px 12px;
      border-radius: 9999px;
      margin-bottom: 12px;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
      letter-spacing: -0.01em;
    }

    .section-subtitle {
      font-size: 1rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* 平台矩阵标签云 */
    .models-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-chip {
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      color: var(--text-main);
      padding: 6px 14px;
      border-radius: 9999px;
      font-size: 0.875rem;
      font-weight: 500;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

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

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

    .feature-card {
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .feature-icon-bar {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 44px;
      height: 44px;
      border-radius: 10px;
      background-color: var(--primary-light);
      color: var(--primary);
      font-size: 1.25rem;
      font-weight: 700;
      margin-bottom: 16px;
    }

    .feature-title {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }

    .feature-desc {
      font-size: 0.938rem;
      color: var(--text-muted);
      line-height: 1.6;
      margin-bottom: 18px;
    }

    .feature-tag {
      font-size: 0.75rem;
      color: #0369a1;
      background-color: #e0f2fe;
      padding: 4px 10px;
      border-radius: 4px;
      align-self: flex-start;
      font-weight: 500;
    }

    /* 素材案例画廊 */
    .gallery-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

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

    .gallery-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-3px);
    }

    .gallery-img-box {
      width: 100%;
      height: 220px;
      background-color: #f1f5f9;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
    }

    .gallery-img-box img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: transform 0.4s ease;
    }

    .gallery-card:hover .gallery-img-box img {
      transform: scale(1.04);
    }

    .gallery-info {
      padding: 20px;
    }

    .gallery-info h3 {
      font-size: 1.125rem;
      font-weight: 700;
      margin-bottom: 6px;
      color: var(--text-main);
    }

    .gallery-info p {
      font-size: 0.875rem;
      color: var(--text-muted);
      line-height: 1.5;
    }

    /* 标准制作流程 */
    .flow-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

    .flow-step-card {
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px 20px;
      position: relative;
      box-shadow: var(--shadow-sm);
    }

    .step-badge {
      font-size: 0.75rem;
      font-weight: 800;
      color: var(--primary);
      background-color: var(--primary-light);
      padding: 3px 8px;
      border-radius: 4px;
      display: inline-block;
      margin-bottom: 12px;
    }

    .step-title {
      font-size: 1.125rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .step-desc {
      font-size: 0.875rem;
      color: var(--text-muted);
      line-height: 1.5;
    }

    /* 对比评测卡片与表格 */
    .rating-banner {
      background: linear-gradient(135deg, #1e3a8a 0%, #2563eb 100%);
      color: #ffffff;
      border-radius: var(--radius-lg);
      padding: 36px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 32px;
      box-shadow: var(--shadow-lg);
    }

    .rating-left h3 {
      font-size: 1.75rem;
      font-weight: 800;
      margin-bottom: 8px;
    }

    .rating-left p {
      font-size: 1rem;
      color: #bfdbfe;
    }

    .rating-scores {
      display: flex;
      align-items: center;
      gap: 24px;
    }

    .rating-item {
      text-align: right;
    }

    .rating-stars {
      color: #fcd34d;
      font-size: 1.5rem;
      letter-spacing: 2px;
    }

    .rating-num {
      font-size: 2.25rem;
      font-weight: 900;
      line-height: 1;
      color: #ffffff;
    }

    .rating-sub {
      font-size: 0.875rem;
      color: #93c5fd;
    }

    .comparison-table-wrap {
      overflow-x: auto;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      background-color: #ffffff;
      box-shadow: var(--shadow-sm);
    }

    .comparison-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.938rem;
    }

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

    .comparison-table th {
      background-color: #f8fafc;
      color: var(--text-main);
      font-weight: 700;
    }

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

    .highlight-col {
      background-color: #f0f7ff;
      font-weight: 600;
      color: var(--primary);
    }

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

    .testimonial-card {
      background-color: #ffffff;
      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;
    }

    .testi-header {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
    }

    .testi-avatar {
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: linear-gradient(135deg, #3b82f6 0%, #1d4ed8 100%);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1rem;
    }

    .testi-meta h4 {
      font-size: 1rem;
      font-weight: 700;
      color: var(--text-main);
    }

    .testi-meta span {
      font-size: 0.813rem;
      color: var(--text-sub);
    }

    .testi-body {
      font-size: 0.938rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

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

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

    .faq-question {
      width: 100%;
      text-align: left;
      padding: 18px 24px;
      background: none;
      border: none;
      font-size: 1.063rem;
      font-weight: 600;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
    }

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

    .faq-icon {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--text-sub);
      transition: var(--transition);
      line-height: 1;
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease-out;
      background-color: #f8fafc;
    }

    .faq-answer-inner {
      padding: 16px 24px 20px;
      font-size: 0.938rem;
      color: var(--text-muted);
      line-height: 1.6;
      border-top: 1px solid var(--border-color);
    }

    /* 表单与联络双列 */
    .contact-wrapper {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 40px;
      box-shadow: var(--shadow-sm);
    }

    .contact-info-panel h3 {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }

    .contact-info-panel p {
      font-size: 0.938rem;
      color: var(--text-muted);
      margin-bottom: 24px;
      line-height: 1.6;
    }

    .contact-channels {
      display: flex;
      flex-direction: column;
      gap: 14px;
      margin-bottom: 28px;
    }

    .channel-item {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 0.938rem;
      color: var(--text-main);
    }

    .channel-label {
      font-weight: 600;
      width: 90px;
      color: var(--text-sub);
    }

    .channel-val {
      font-weight: 500;
    }

    .qrcode-box {
      border: 1px dashed var(--border-color);
      border-radius: var(--radius-md);
      padding: 16px;
      display: inline-flex;
      flex-direction: column;
      align-items: center;
      gap: 10px;
      background-color: #f8fafc;
    }

    .qrcode-box img {
      width: 130px;
      height: 130px;
      object-fit: cover;
      display: block;
      border-radius: var(--radius-sm);
    }

    .qrcode-tip {
      font-size: 0.813rem;
      color: var(--text-sub);
      font-weight: 500;
    }

    .form-panel form {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .form-group {
      display: flex;
      flex-direction: column;
      gap: 6px;
    }

    .form-group label {
      font-size: 0.875rem;
      font-weight: 600;
      color: var(--text-main);
    }

    .form-control {
      width: 100%;
      padding: 12px 14px;
      font-size: 0.938rem;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      outline: none;
      background-color: #ffffff;
      color: var(--text-main);
      transition: var(--transition);
    }

    .form-control:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
    }

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

    .btn-submit {
      padding: 14px 24px;
      font-size: 1rem;
      font-weight: 700;
      color: #ffffff;
      background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
      border: none;
      border-radius: var(--radius-sm);
      cursor: pointer;
      box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
      transition: var(--transition);
    }

    .btn-submit:hover {
      background: linear-gradient(135deg, #1d4ed8 0%, #1e40af 100%);
      transform: translateY(-1px);
    }

    /* 资讯与外链 */
    .news-link-grid {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 14px;
      margin-top: 24px;
    }

    .news-item {
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 16px;
      font-size: 0.875rem;
      color: var(--text-main);
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      gap: 8px;
    }

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

    /* 友情链接与通用尾部 */
    .footer-section {
      background-color: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 48px 0 32px;
      font-size: 0.875rem;
      color: var(--text-muted);
    }

    .footer-top-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 36px;
    }

    .footer-brand h4 {
      font-size: 1.125rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }

    .footer-brand p {
      line-height: 1.6;
      max-width: 440px;
    }

    .footer-links-col h4 {
      font-size: 0.938rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }

    .footer-links-col ul {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

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

    .friend-links-box {
      border-top: 1px solid var(--border-color);
      padding-top: 24px;
      margin-bottom: 24px;
    }

    .friend-links-title {
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 10px;
      font-size: 0.875rem;
    }

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

    .friend-links-list a {
      color: var(--text-sub);
      text-decoration: none;
    }

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

    .footer-bottom {
      border-top: 1px solid var(--border-color);
      padding-top: 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      color: var(--text-sub);
      font-size: 0.813rem;
    }

    /* 悬浮工具栏 */
    .float-toolbar {
      position: fixed;
      right: 20px;
      bottom: 40px;
      z-index: 99;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--text-main);
      box-shadow: var(--shadow-md);
      cursor: pointer;
      transition: var(--transition);
      font-size: 1.125rem;
    }

    .float-btn:hover {
      background-color: var(--primary);
      color: #ffffff;
      border-color: var(--primary);
      transform: translateY(-2px);
    }

    /* 响应式断点 */
    @media (max-width: 992px) {
      .hero-title {
        font-size: 2rem;
      }
      .hero-metrics-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .feature-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .gallery-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .flow-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .testimonial-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .contact-wrapper {
        grid-template-columns: 1fr;
      }
      .news-link-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-top-grid {
        grid-template-columns: 1fr;
        gap: 24px;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background-color: #ffffff;
        flex-direction: column;
        padding: 16px 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.open {
        display: flex;
      }
      .mobile-menu-btn {
        display: block;
      }
      .feature-grid, .gallery-grid, .testimonial-grid, .hero-metrics-grid, .flow-grid {
        grid-template-columns: 1fr;
      }
      .rating-banner {
        flex-direction: column;
        align-items: flex-start;
        gap: 20px;
      }
      .rating-item {
        text-align: left;
      }
      .news-link-grid {
        grid-template-columns: 1fr;
      }
      .footer-bottom {
        flex-direction: column;
        gap: 12px;
        text-align: center;
      }
    }