:root {
      --primary: #4f46e5;
      --primary-dark: #3730a3;
      --accent-cyan: #06b6d4;
      --accent-rose: #f43f5e;
      --accent-amber: #f59e0b;
      --accent-purple: #8b5cf6;
      --bg-main: #f8fafc;
      --bg-card: #ffffff;
      --bg-subtle: #f1f5f9;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-light: #64748b;
      --border-color: #e2e8f0;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
      --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 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(0,0,0,0.04);
      --max-width: 1200px;
      --radius: 12px;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      -webkit-tap-highlight-color: transparent;
    }

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

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background: var(--bg-main);
      color: var(--text-main);
      line-height: 1.6;
      overflow-x: hidden;
    }

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

    /* 顶部导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .nav-inner {
      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;
    }

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

    .nav-links li a {
      color: var(--text-main);
      text-decoration: none;
      font-size: 0.95rem;
      font-weight: 500;
      padding: 8px 14px;
      border-radius: 6px;
      transition: all 0.2s ease;
      white-space: nowrap;
    }

    .nav-links li a:hover,
    .nav-links li a.ai-page-home-link {
      color: var(--primary);
      background: #eef2ff;
    }

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

    .btn-nav-primary {
      display: inline-block;
      padding: 9px 20px;
      background: linear-gradient(135deg, var(--primary), var(--accent-purple));
      color: #ffffff;
      text-decoration: none;
      border-radius: 8px;
      font-weight: 600;
      font-size: 0.95rem;
      box-shadow: 0 2px 6px rgba(79, 70, 229, 0.3);
      transition: transform 0.2s ease, box-shadow 0.2s ease;
    }

    .btn-nav-primary:hover {
      transform: translateY(-1px);
      box-shadow: 0 4px 10px rgba(79, 70, 229, 0.4);
    }

    .mobile-menu-toggle {
      display: none;
      background: none;
      border: 1px solid var(--border-color);
      border-radius: 6px;
      padding: 8px;
      cursor: pointer;
      color: var(--text-main);
    }

    /* 斑斓视觉主基调背景容器 */
    .section-wrap {
      padding: 64px 0;
      position: relative;
    }

    .section-wrap-alt {
      background: #f1f5f9;
      border-top: 1px solid var(--border-color);
      border-bottom: 1px solid var(--border-color);
    }

    .section-header {
      text-align: center;
      margin-bottom: 44px;
    }

    .section-badge {
      display: inline-block;
      padding: 4px 14px;
      border-radius: 999px;
      font-size: 0.85rem;
      font-weight: 600;
      color: var(--primary);
      background: #e0e7ff;
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .section-title {
      font-size: 2.1rem;
      color: var(--text-main);
      font-weight: 800;
      letter-spacing: -0.5px;
      margin-bottom: 12px;
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
      max-width: 720px;
      margin: 0 auto;
    }

    /* Hero 首屏 - 纯 CSS 科技几何构图，无任何图片 */
    .hero-section {
      padding: 80px 0 60px;
      background: radial-gradient(circle at 85% 15%, rgba(6, 182, 212, 0.12) 0%, transparent 40%),
                  radial-gradient(circle at 10% 80%, rgba(244, 63, 94, 0.1) 0%, transparent 40%),
                  linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
      border-bottom: 1px solid var(--border-color);
      position: relative;
    }

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

    .hero-content h1 {
      font-size: 2.4rem;
      line-height: 1.25;
      font-weight: 900;
      color: var(--text-main);
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-lead {
      font-size: 1.15rem;
      color: var(--text-muted);
      margin-bottom: 28px;
      line-height: 1.7;
    }

    .hero-btn-group {
      display: flex;
      flex-wrap: wrap;
      gap: 14px;
      margin-bottom: 36px;
    }

    .btn-hero-official {
      padding: 14px 30px;
      font-size: 1.1rem;
      font-weight: 700;
      border-radius: 10px;
      text-decoration: none;
      background: linear-gradient(135deg, #4f46e5, #06b6d4);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(79, 70, 229, 0.35);
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }

    .btn-hero-official:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(79, 70, 229, 0.45);
    }

    .btn-hero-outline {
      padding: 14px 26px;
      font-size: 1.05rem;
      font-weight: 600;
      border-radius: 10px;
      text-decoration: none;
      background: #ffffff;
      color: var(--text-main);
      border: 2px solid var(--border-color);
      transition: all 0.25s ease;
    }

    .btn-hero-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
    }

    .hero-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
    }

    .tag-chip {
      padding: 5px 12px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 6px;
      font-size: 0.85rem;
      color: var(--text-muted);
      font-weight: 500;
      box-shadow: var(--shadow-sm);
    }

    /* 首屏纯样式动态卡片面板（无图片） */
    .hero-panel {
      background: #ffffff;
      border: 1px solid rgba(79, 70, 229, 0.15);
      border-radius: 16px;
      padding: 24px;
      box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.03);
      position: relative;
    }

    .panel-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 20px;
      padding-bottom: 12px;
      border-bottom: 1px solid var(--border-color);
    }

    .panel-dots {
      display: flex;
      gap: 6px;
    }

    .panel-dots span {
      width: 10px;
      height: 10px;
      border-radius: 50%;
      background: #cbd5e1;
    }

    .panel-dots span:nth-child(1) { background: #f87171; }
    .panel-dots span:nth-child(2) { background: #fbbf24; }
    .panel-dots span:nth-child(3) { background: #34d399; }

    .panel-status {
      font-size: 0.8rem;
      color: #059669;
      font-weight: 600;
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .panel-status::before {
      content: "";
      display: inline-block;
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #10b981;
      box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.2);
    }

    .panel-features-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .panel-feature-item {
      padding: 12px 14px;
      border-radius: 8px;
      background: var(--bg-subtle);
      display: flex;
      align-items: center;
      justify-content: space-between;
      border-left: 4px solid var(--primary);
    }

    .panel-feature-item:nth-child(2) { border-left-color: var(--accent-cyan); }
    .panel-feature-item:nth-child(3) { border-left-color: var(--accent-rose); }
    .panel-feature-item:nth-child(4) { border-left-color: var(--accent-amber); }

    .feature-item-title {
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-main);
    }

    .feature-item-badge {
      font-size: 0.75rem;
      padding: 2px 8px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 4px;
      color: var(--text-muted);
    }

    /* 指标统计条 */
    .metrics-bar {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      margin-top: 36px;
    }

    .metric-card {
      background: #ffffff;
      padding: 18px 20px;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      text-align: center;
      box-shadow: var(--shadow-sm);
    }

    .metric-num {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 4px;
    }

    .metric-label {
      font-size: 0.85rem;
      color: var(--text-muted);
      font-weight: 500;
    }

    /* 网格通用卡片 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 22px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 18px;
    }

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

    .card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      transition: all 0.25s ease;
      position: relative;
    }

    .card:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(79, 70, 229, 0.3);
    }

    .card-icon {
      width: 44px;
      height: 44px;
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.3rem;
      margin-bottom: 16px;
      background: #e0e7ff;
      color: var(--primary);
    }

    .card-title {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }

    .card-text {
      font-size: 0.92rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* 多模型生态展示条 */
    .models-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      padding: 20px;
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .model-chip {
      padding: 6px 14px;
      border-radius: 8px;
      font-size: 0.85rem;
      font-weight: 600;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      color: var(--text-main);
      transition: all 0.2s ease;
    }

    .model-chip:hover {
      background: #e0e7ff;
      color: var(--primary);
      border-color: #c7d2fe;
    }

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

    .step-item {
      background: #ffffff;
      padding: 24px;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      position: relative;
    }

    .step-number {
      font-size: 1.6rem;
      font-weight: 900;
      color: var(--primary);
      opacity: 0.8;
      margin-bottom: 10px;
    }

    .step-item h3 {
      font-size: 1.05rem;
      margin-bottom: 8px;
    }

    /* 对比评测高亮卡片与表格 */
    .eval-overview-card {
      background: linear-gradient(135deg, #4338ca, #3b82f6);
      border-radius: 16px;
      padding: 32px;
      color: #ffffff;
      margin-bottom: 30px;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
      box-shadow: 0 10px 25px -5px rgba(67, 56, 202, 0.4);
    }

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

    .eval-big-score {
      font-size: 3.8rem;
      font-weight: 900;
      line-height: 1;
      color: #fbbf24;
    }

    .eval-score-text {
      font-size: 1.1rem;
      opacity: 0.95;
    }

    .eval-stars {
      color: #fbbf24;
      font-size: 1.4rem;
      letter-spacing: 2px;
    }

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

    .custom-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.92rem;
    }

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

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

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

    .badge-highlight {
      background: #ecfdf5;
      color: #059669;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: 6px;
      display: inline-block;
    }

    /* 案例展示区 */
    .case-card {
      background: #ffffff;
      border-radius: var(--radius);
      overflow: hidden;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .case-media-box {
      width: 100%;
      background: #e2e8f0;
      overflow: hidden;
    }

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

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

    .case-body {
      padding: 20px;
    }

    .case-tag {
      font-size: 0.75rem;
      font-weight: 600;
      color: var(--accent-rose);
      text-transform: uppercase;
      margin-bottom: 6px;
      display: block;
    }

    /* FAQ 折叠面板 */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 14px;
      max-width: 900px;
      margin: 0 auto;
    }

    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 10px;
      overflow: hidden;
      transition: border-color 0.2s;
    }

    .faq-item.active {
      border-color: var(--primary);
    }

    .faq-question {
      padding: 18px 22px;
      font-weight: 700;
      font-size: 1rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
      color: var(--text-main);
    }

    .faq-question::after {
      content: "+";
      font-size: 1.4rem;
      font-weight: 400;
      color: var(--primary);
      transition: transform 0.2s;
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease-out, padding 0.3s ease;
      background: #f8fafc;
      color: var(--text-muted);
      font-size: 0.95rem;
      line-height: 1.7;
    }

    .faq-item.active .faq-answer {
      max-height: 250px;
      padding: 16px 22px 20px;
      border-top: 1px solid var(--border-color);
    }

    /* 评论卡片 */
    .review-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 22px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .review-author {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid #f1f5f9;
      padding-top: 12px;
    }

    .author-avatar-text {
      width: 38px;
      height: 38px;
      border-radius: 50%;
      background: #e0e7ff;
      color: var(--primary);
      font-weight: 700;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 0.95rem;
    }

    .author-info h4 {
      font-size: 0.9rem;
      color: var(--text-main);
    }

    .author-info span {
      font-size: 0.75rem;
      color: var(--text-light);
    }

    /* 表单与转化区 */
    .form-wrapper {
      background: #ffffff;
      border-radius: 16px;
      border: 1px solid var(--border-color);
      padding: 36px;
      box-shadow: var(--shadow-md);
      max-width: 800px;
      margin: 0 auto;
    }

    .form-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 18px;
    }

    .form-group-full {
      grid-column: span 2;
    }

    .form-label {
      display: block;
      font-size: 0.88rem;
      font-weight: 600;
      margin-bottom: 6px;
      color: var(--text-main);
    }

    .form-control {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      font-size: 0.95rem;
      color: var(--text-main);
      outline: none;
      transition: border-color 0.2s ease;
      background: #f8fafc;
    }

    .form-control:focus {
      border-color: var(--primary);
      background: #ffffff;
    }

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

    .btn-submit {
      width: 100%;
      padding: 14px;
      background: linear-gradient(135deg, var(--primary), var(--primary-dark));
      color: #ffffff;
      border: none;
      border-radius: 8px;
      font-size: 1rem;
      font-weight: 700;
      cursor: pointer;
      transition: opacity 0.2s ease;
    }

    .btn-submit:hover {
      opacity: 0.92;
    }

    /* 文章与资讯列表 */
    .article-box {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 20px;
    }

    .article-links-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 14px;
    }

    .article-pill {
      padding: 8px 14px;
      background: #f1f5f9;
      border-radius: 6px;
      font-size: 0.85rem;
      color: var(--text-muted);
      text-decoration: none;
      transition: all 0.2s;
    }

    .article-pill:hover {
      background: #e0e7ff;
      color: var(--primary);
    }

    /* 浮动客服入口 */
    .float-service-card {
      position: fixed;
      right: 20px;
      bottom: 80px;
      z-index: 990;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 12px;
      padding: 14px;
      box-shadow: var(--shadow-lg);
      text-align: center;
      width: 140px;
      transition: transform 0.2s;
    }

    .float-service-card:hover {
      transform: translateY(-3px);
    }

    .float-service-card img {
      width: 90px;
      height: 90px;
      display: block;
      margin: 0 auto 8px;
      border-radius: 4px;
    }

    .float-service-card p {
      font-size: 0.78rem;
      font-weight: 600;
      color: var(--text-main);
    }

    /* 页脚 */
    .site-footer {
      background: #0f172a;
      color: #94a3b8;
      padding: 50px 0 24px;
      border-top: 1px solid #1e293b;
    }

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

    .footer-col h4 {
      color: #ffffff;
      font-size: 1rem;
      margin-bottom: 16px;
      font-weight: 600;
    }

    .footer-col p {
      font-size: 0.88rem;
      line-height: 1.7;
      margin-bottom: 10px;
    }

    .footer-col ul {
      list-style: none;
      padding: 0;
    }

    .footer-col ul li {
      margin-bottom: 8px;
    }

    .footer-col ul li a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.88rem;
      transition: color 0.2s;
    }

    .footer-col ul li a:hover {
      color: #ffffff;
    }

    .friend-links-area {
      border-top: 1px solid #1e293b;
      padding-top: 20px;
      margin-bottom: 20px;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 12px;
      font-size: 0.85rem;
    }

    .friend-links-area a {
      color: #94a3b8;
      text-decoration: none;
      transition: color 0.2s;
    }

    .friend-links-area a:hover {
      color: #38bdf8;
    }

    .copyright-area {
      border-top: 1px solid #1e293b;
      padding-top: 20px;
      text-align: center;
      font-size: 0.82rem;
      color: #64748b;
    }

    /* 响应式调整 */
    @media (max-width: 992px) {
      .hero-grid {
        grid-template-columns: 1fr;
        gap: 30px;
      }
      .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: 1fr 1fr;
      }
      .metrics-bar {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .nav-links.mobile-open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        border-bottom: 1px solid var(--border-color);
        padding: 16px 20px;
        box-shadow: var(--shadow-md);
      }
      .mobile-menu-toggle {
        display: block;
      }
      .hero-content h1 {
        font-size: 1.8rem;
      }
      .section-title {
        font-size: 1.6rem;
      }
      .grid-3, .grid-2, .steps-container {
        grid-template-columns: 1fr;
      }
      .form-grid {
        grid-template-columns: 1fr;
      }
      .form-group-full {
        grid-column: span 1;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .float-service-card {
        display: none;
      }
    }