:root {
      --bg-base: #f8fafc;
      --bg-surface: #ffffff;
      --bg-alt: #f1f5f9;
      --color-primary: #0284c7;
      --color-accent: #f97316;
      --color-contrast: #6366f1;
      --color-success: #10b981;
      --color-dark: #0f172a;
      --color-text: #1e293b;
      --color-muted: #64748b;
      --color-border: #e2e8f0;
      --color-border-bright: #cbd5e1;
      --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.08);
      --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.08);
      --shadow-lg: 0 10px 25px -5px rgba(15, 23, 42, 0.12);
      --shadow-pop: 4px 4px 0px #0f172a;
      --radius: 12px;
      --radius-sm: 6px;
      --radius-lg: 20px;
      --container-width: 1200px;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }

    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-base);
      color: var(--color-text);
      line-height: 1.6;
      overflow-x: hidden;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: all 0.2s ease;
    }

    .container {
      width: 100%;
      max-width: var(--container-width);
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 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: 2px solid var(--color-dark);
      box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    }

    .nav-wrapper {
      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: 38px;
      width: auto;
      display: block;
    }

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

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

    .nav-links li a {
      font-size: 14px;
      font-weight: 600;
      color: var(--color-text);
      padding: 8px 12px;
      border-radius: var(--radius-sm);
      display: inline-block;
    }

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

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 14px;
      padding: 10px 20px;
      border-radius: var(--radius-sm);
      cursor: pointer;
      transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
      border: 2px solid var(--color-dark);
      text-align: center;
      white-space: nowrap;
    }

    .btn-contrast {
      background-color: var(--color-accent);
      color: #ffffff;
      box-shadow: var(--shadow-pop);
    }

    .btn-contrast:hover {
      transform: translate(-2px, -2px);
      box-shadow: 6px 6px 0px var(--color-dark);
    }

    .btn-primary {
      background-color: var(--color-primary);
      color: #ffffff;
      box-shadow: var(--shadow-pop);
    }

    .btn-primary:hover {
      transform: translate(-2px, -2px);
      box-shadow: 6px 6px 0px var(--color-dark);
    }

    .btn-outline {
      background-color: #ffffff;
      color: var(--color-dark);
      box-shadow: 2px 2px 0px var(--color-dark);
    }

    .btn-outline:hover {
      background-color: var(--bg-alt);
      transform: translate(-1px, -1px);
    }

    .menu-toggle {
      display: none;
      background: none;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius-sm);
      padding: 6px 10px;
      font-size: 18px;
      font-weight: 700;
      cursor: pointer;
    }

    /* 首屏 Hero 区域 (绝无图片) */
    .hero-section {
      padding: 70px 0 50px;
      background: linear-gradient(135deg, #f0fdf4 0%, #e0f2fe 50%, #fef3c7 100%);
      border-bottom: 2px solid var(--color-dark);
      position: relative;
      overflow: hidden;
    }

    .hero-badge-wrap {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 16px;
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: 30px;
      box-shadow: 3px 3px 0px var(--color-dark);
      margin-bottom: 24px;
      font-weight: 700;
      font-size: 13px;
      color: var(--color-accent);
    }

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

    .hero-title {
      font-size: 42px;
      line-height: 1.25;
      font-weight: 900;
      color: var(--color-dark);
      margin-bottom: 20px;
      letter-spacing: -1px;
    }

    .hero-title span {
      background: linear-gradient(90deg, #f97316, #6366f1);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-desc {
      font-size: 18px;
      color: var(--color-text);
      max-width: 760px;
      margin: 0 auto 32px;
      line-height: 1.7;
    }

    .hero-actions {
      display: flex;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 40px;
    }

    .hero-actions .btn {
      padding: 14px 32px;
      font-size: 16px;
    }

    .model-tags-bar {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 8px;
      padding: 16px;
      background: rgba(255, 255, 255, 0.85);
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      box-shadow: var(--shadow-pop);
      margin-top: 20px;
    }

    .model-tag {
      font-size: 12px;
      font-weight: 700;
      padding: 4px 10px;
      background: #ffffff;
      border: 1px solid var(--color-dark);
      border-radius: 4px;
      color: var(--color-dark);
    }

    .model-tag.highlight {
      background: #ffedd5;
      color: #c2410c;
    }

    /* Section 通用 */
    .section {
      padding: 64px 0;
      border-bottom: 2px solid var(--color-dark);
    }

    .section-alt {
      background-color: var(--bg-surface);
    }

    .section-accent {
      background-color: #fefce8;
    }

    .section-head {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 40px;
    }

    .section-badge {
      display: inline-block;
      padding: 4px 14px;
      background: var(--color-dark);
      color: #ffffff;
      font-size: 12px;
      font-weight: 800;
      border-radius: 4px;
      margin-bottom: 12px;
      text-transform: uppercase;
      letter-spacing: 1px;
    }

    .section-title {
      font-size: 30px;
      font-weight: 800;
      color: var(--color-dark);
      margin-bottom: 12px;
    }

    .section-subtitle {
      font-size: 16px;
      color: var(--color-muted);
    }

    /* 数据指标网格 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-bottom: 10px;
    }

    .stat-card {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      padding: 24px 20px;
      text-align: center;
      box-shadow: var(--shadow-pop);
      transition: transform 0.2s ease;
    }

    .stat-card:hover {
      transform: translateY(-4px);
    }

    .stat-value {
      font-size: 34px;
      font-weight: 900;
      color: var(--color-primary);
      line-height: 1.1;
      margin-bottom: 6px;
    }

    .stat-label {
      font-size: 14px;
      font-weight: 700;
      color: var(--color-dark);
    }

    .stat-desc {
      font-size: 12px;
      color: var(--color-muted);
      margin-top: 4px;
    }

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

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

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
    }

    .feature-card {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow-pop);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      transition: transform 0.2s ease;
    }

    .feature-card:hover {
      transform: translateY(-4px);
    }

    .card-icon-title {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 12px;
    }

    .card-pill {
      display: inline-block;
      padding: 3px 8px;
      font-size: 11px;
      font-weight: 700;
      border-radius: 4px;
      background: #fee2e2;
      color: #b91c1c;
      border: 1px solid #ef4444;
    }

    .feature-card h3 {
      font-size: 18px;
      font-weight: 800;
      color: var(--color-dark);
    }

    .feature-card p {
      font-size: 14px;
      color: var(--color-text);
      line-height: 1.6;
      margin-bottom: 16px;
    }

    .feature-card .card-footer-tag {
      font-size: 12px;
      font-weight: 600;
      color: var(--color-primary);
      border-top: 1px dashed var(--color-border-bright);
      padding-top: 12px;
    }

    /* 撞色高亮卡片 */
    .feature-card.accent-card {
      background: #fff7ed;
      border-color: var(--color-dark);
    }

    .feature-card.indigo-card {
      background: #eef2ff;
      border-color: var(--color-dark);
    }

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

    .step-item {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      padding: 24px 20px;
      box-shadow: var(--shadow-pop);
      position: relative;
    }

    .step-num {
      width: 36px;
      height: 36px;
      background: var(--color-accent);
      color: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 900;
      font-size: 16px;
      margin-bottom: 16px;
      box-shadow: 2px 2px 0 var(--color-dark);
    }

    .step-item h4 {
      font-size: 16px;
      font-weight: 800;
      margin-bottom: 8px;
      color: var(--color-dark);
    }

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

    /* 对比表格 */
    .compare-box {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      box-shadow: var(--shadow-pop);
      overflow-x: auto;
      margin-bottom: 24px;
    }

    .compare-score-banner {
      background: linear-gradient(90deg, #f97316, #fbbf24);
      border-bottom: 2px solid var(--color-dark);
      padding: 20px 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 16px;
    }

    .score-left h3 {
      font-size: 20px;
      font-weight: 900;
      color: var(--color-dark);
    }

    .score-left p {
      font-size: 14px;
      color: #7c2d12;
      font-weight: 700;
    }

    .score-right {
      display: flex;
      align-items: center;
      gap: 12px;
      background: #ffffff;
      border: 2px solid var(--color-dark);
      padding: 8px 16px;
      border-radius: var(--radius-sm);
      box-shadow: 2px 2px 0 var(--color-dark);
    }

    .score-stars {
      color: #f59e0b;
      font-size: 18px;
    }

    .score-num {
      font-size: 22px;
      font-weight: 900;
      color: var(--color-dark);
    }

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

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

    .table-responsive th {
      background: #f8fafc;
      font-weight: 800;
      color: var(--color-dark);
      border-bottom: 2px solid var(--color-dark);
    }

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

    .highlight-col {
      background-color: #f0fdf4;
      font-weight: 700;
      color: #166534;
    }

    /* 图片画廊展示区 (非首屏) */
    .media-showcase {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
      margin-top: 24px;
    }

    .media-card {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      overflow: hidden;
      box-shadow: var(--shadow-pop);
    }

    .media-card .img-holder {
      width: 100%;
      background: #f1f5f9;
      display: flex;
      align-items: center;
      justify-content: center;
      border-bottom: 2px solid var(--color-dark);
    }

    .media-card img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
    }

    .media-card .media-info {
      padding: 16px;
    }

    .media-card h4 {
      font-size: 16px;
      font-weight: 800;
      color: var(--color-dark);
      margin-bottom: 6px;
    }

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

    /* FAQ 折叠面板 */
    .faq-container {
      max-width: 860px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius-sm);
      box-shadow: 2px 2px 0 var(--color-dark);
      overflow: hidden;
    }

    .faq-question {
      padding: 18px 20px;
      font-size: 16px;
      font-weight: 800;
      color: var(--color-dark);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: #ffffff;
      transition: background-color 0.2s;
    }

    .faq-question:hover {
      background: #f8fafc;
    }

    .faq-icon {
      font-size: 18px;
      font-weight: 900;
      transition: transform 0.2s ease;
    }

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

    .faq-answer {
      display: none;
      padding: 16px 20px;
      font-size: 14px;
      line-height: 1.7;
      color: var(--color-text);
      background: #fdfdfd;
      border-top: 1px dashed var(--color-border);
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    /* 用户评论 */
    .reviews-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
    }

    .review-card {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      padding: 20px;
      box-shadow: var(--shadow-pop);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .review-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: #fed7aa;
      border: 2px solid var(--color-dark);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 900;
      color: #9a3412;
    }

    .reviewer-name {
      font-weight: 800;
      font-size: 15px;
      color: var(--color-dark);
    }

    .reviewer-role {
      font-size: 12px;
      color: var(--color-muted);
    }

    .review-body {
      font-size: 13px;
      color: var(--color-text);
      line-height: 1.6;
      margin-bottom: 12px;
    }

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

    /* 表单与联系区 */
    .contact-wrapper {
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      gap: 32px;
      align-items: start;
    }

    .contact-info-card {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      padding: 28px;
      box-shadow: var(--shadow-pop);
    }

    .contact-info-card h3 {
      font-size: 20px;
      font-weight: 900;
      margin-bottom: 16px;
      color: var(--color-dark);
    }

    .contact-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 14px;
      font-size: 14px;
      margin-bottom: 24px;
    }

    .contact-list li {
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .contact-list li strong {
      color: var(--color-dark);
    }

    .qrcode-box {
      border: 2px dashed var(--color-dark);
      border-radius: var(--radius-sm);
      padding: 16px;
      text-align: center;
      background: #f8fafc;
    }

    .qrcode-box img {
      width: 140px;
      height: 140px;
      display: block;
      margin: 0 auto 10px;
      border: 1px solid var(--color-border);
    }

    .qrcode-box p {
      font-size: 12px;
      font-weight: 700;
      color: var(--color-dark);
    }

    .form-card {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      padding: 28px;
      box-shadow: var(--shadow-pop);
    }

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

    .form-group label {
      display: block;
      font-size: 13px;
      font-weight: 800;
      color: var(--color-dark);
      margin-bottom: 6px;
    }

    .form-input, .form-select, .form-textarea {
      width: 100%;
      padding: 10px 14px;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius-sm);
      font-size: 14px;
      font-family: inherit;
      background-color: #f8fafc;
      transition: border-color 0.2s;
    }

    .form-input:focus, .form-select:focus, .form-textarea:focus {
      outline: none;
      background-color: #ffffff;
      border-color: var(--color-primary);
    }

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

    /* 资讯与百科 */
    .news-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .news-card {
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: var(--radius);
      padding: 20px;
      box-shadow: var(--shadow-pop);
    }

    .news-card h3 {
      font-size: 17px;
      font-weight: 800;
      margin-bottom: 12px;
      color: var(--color-dark);
    }

    .news-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .news-list li a {
      font-size: 13px;
      color: var(--color-text);
      display: flex;
      justify-content: space-between;
      padding: 6px 0;
      border-bottom: 1px dotted var(--color-border);
    }

    .news-list li a:hover {
      color: var(--color-primary);
    }

    /* 友情链接与页脚 */
    .site-footer {
      background-color: #ffffff;
      border-top: 2px solid var(--color-dark);
      padding: 40px 0 24px;
      color: var(--color-text);
    }

    .footer-links-section {
      border-bottom: 1px solid var(--color-border);
      padding-bottom: 24px;
      margin-bottom: 24px;
    }

    .footer-title {
      font-size: 14px;
      font-weight: 800;
      color: var(--color-dark);
      margin-bottom: 12px;
    }

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

    .links-cloud a {
      font-size: 13px;
      color: var(--color-muted);
      background: var(--bg-alt);
      padding: 4px 10px;
      border-radius: 4px;
      border: 1px solid var(--color-border);
    }

    .links-cloud a:hover {
      color: var(--color-primary);
      border-color: var(--color-dark);
    }

    .footer-bottom {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 16px;
      font-size: 13px;
      color: var(--color-muted);
    }

    .footer-copy {
      font-weight: 600;
      color: var(--color-dark);
    }

    /* 浮动工具栏 */
    .floating-toolbar {
      position: fixed;
      right: 20px;
      bottom: 30px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      z-index: 999;
    }

    .float-btn {
      width: 46px;
      height: 46px;
      background: #ffffff;
      border: 2px solid var(--color-dark);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 14px;
      font-weight: 800;
      box-shadow: 2px 2px 0 var(--color-dark);
      cursor: pointer;
      color: var(--color-dark);
      transition: transform 0.2s;
    }

    .float-btn:hover {
      transform: scale(1.1);
      background: var(--color-accent);
      color: #ffffff;
    }

    /* 响应式调整 */
    @media (max-width: 992px) {
      .grid-4, .steps-wrapper, .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3, .reviews-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .contact-wrapper {
        grid-template-columns: 1fr;
      }
      .hero-title {
        font-size: 32px;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        border-bottom: 2px solid var(--color-dark);
        flex-direction: column;
        align-items: flex-start;
        padding: 16px 20px;
      }
      .nav-links.show {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .grid-3, .grid-4, .grid-2, .steps-wrapper, .stats-grid, .reviews-grid, .media-showcase, .news-grid {
        grid-template-columns: 1fr;
      }
      .hero-title {
        font-size: 26px;
      }
      .hero-desc {
        font-size: 15px;
      }
      .footer-bottom {
        flex-direction: column;
        align-items: flex-start;
      }
    }