:root {
      --bg-main: #faf8f5;
      --bg-card: #ffffff;
      --bg-tint-yellow: #fef08a;
      --bg-tint-blue: #e0f2fe;
      --bg-tint-pink: #fce7f3;
      --bg-tint-green: #dcfce7;
      --bg-tint-orange: #ffedd5;
      --text-main: #18181b;
      --text-muted: #52525b;
      --text-sub: #71717a;
      --border-dark: #18181b;
      --primary-color: #2563eb;
      --accent-yellow: #facc15;
      --accent-coral: #fb7185;
      --accent-green: #22c55e;
      --accent-purple: #a855f7;
      --shadow-solid: 4px 4px 0px #18181b;
      --shadow-solid-lg: 6px 6px 0px #18181b;
      --shadow-solid-sm: 2px 2px 0px #18181b;
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
      --radius-pill: 9999px;
      --container-max: 1200px;
    }

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

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

    body {
      background-color: var(--bg-main);
      background-image: radial-gradient(#e4e4e7 1px, transparent 1px);
      background-size: 24px 24px;
      color: var(--text-main);
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

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

    /* 涂鸦风徽章与标签 */
    .graffiti-tag {
      display: inline-block;
      font-weight: 700;
      font-size: 0.85rem;
      padding: 4px 12px;
      border-radius: var(--radius-pill);
      border: 2px solid var(--border-dark);
      background-color: var(--bg-tint-yellow);
      box-shadow: var(--shadow-solid-sm);
      margin-bottom: 12px;
    }

    .graffiti-box {
      background: var(--bg-card);
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-solid);
      transition: transform 0.2s ease, box-shadow 0.2s ease;
    }

    .graffiti-box:hover {
      transform: translate(-2px, -2px);
      box-shadow: var(--shadow-solid-lg);
    }

    /* 按钮规范 */
    .btn-main {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 28px;
      font-weight: 800;
      font-size: 1rem;
      text-decoration: none;
      color: var(--text-main);
      background-color: var(--accent-yellow);
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-pill);
      box-shadow: var(--shadow-solid);
      cursor: pointer;
      transition: transform 0.15s ease, box-shadow 0.15s ease, background-color 0.15s ease;
    }

    .btn-main:hover {
      background-color: #fde047;
      transform: translate(-2px, -2px);
      box-shadow: var(--shadow-solid-lg);
    }

    .btn-main:active {
      transform: translate(2px, 2px);
      box-shadow: var(--shadow-solid-sm);
    }

    .btn-secondary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 28px;
      font-weight: 700;
      font-size: 1rem;
      text-decoration: none;
      color: var(--text-main);
      background-color: #ffffff;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-pill);
      box-shadow: var(--shadow-solid);
      cursor: pointer;
      transition: transform 0.15s ease, box-shadow 0.15s ease;
    }

    .btn-secondary:hover {
      background-color: #f4f4f5;
      transform: translate(-2px, -2px);
      box-shadow: var(--shadow-solid-lg);
    }

    /* 顶部导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(250, 248, 245, 0.95);
      backdrop-filter: blur(8px);
      border-bottom: 2px solid var(--border-dark);
    }

    .nav-wrapper {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 76px;
    }

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

    .ai-page-logo {
      height: 42px;
      width: auto;
      border-radius: 6px;
    }

    .brand-name {
      font-size: 1.35rem;
      font-weight: 900;
      letter-spacing: -0.5px;
    }

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

    .nav-links li {
      margin: 0;
      padding: 0;
    }

    .nav-links a {
      text-decoration: none;
      color: var(--text-main);
      font-weight: 700;
      font-size: 0.92rem;
      padding: 8px 14px;
      border-radius: var(--radius-pill);
      transition: background-color 0.2s;
    }

    .nav-links a:hover {
      background-color: var(--bg-tint-yellow);
    }

    .nav-actions {
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .mobile-menu-btn {
      display: none;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      padding: 8px 12px;
      font-weight: 800;
      border-radius: var(--radius-sm);
      cursor: pointer;
      box-shadow: var(--shadow-solid-sm);
    }

    /* 标题区域通用 */
    .section-head {
      text-align: center;
      margin-bottom: 48px;
    }

    .section-head h2 {
      font-size: 2rem;
      font-weight: 900;
      margin-bottom: 12px;
      position: relative;
      display: inline-block;
    }

    .section-head h2::after {
      content: "";
      position: absolute;
      bottom: -6px;
      left: 15%;
      width: 70%;
      height: 6px;
      background: var(--accent-yellow);
      border: 2px solid var(--border-dark);
      border-radius: 4px;
      z-index: -1;
    }

    .section-head p {
      color: var(--text-muted);
      font-size: 1.05rem;
      max-width: 680px;
      margin: 0 auto;
    }

    /* 首屏 Hero */
    .hero-section {
      padding: 70px 0 60px;
      position: relative;
    }

    .hero-box {
      background: #ffffff;
      border: 3px solid var(--border-dark);
      border-radius: var(--radius-lg);
      padding: 50px 36px;
      box-shadow: var(--shadow-solid-lg);
      text-align: center;
      position: relative;
      overflow: hidden;
    }

    .hero-decor-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      padding: 6px 16px;
      background: var(--bg-tint-pink);
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-pill);
      font-weight: 800;
      font-size: 0.9rem;
      margin-bottom: 20px;
    }

    .hero-title {
      font-size: 2.3rem;
      font-weight: 900;
      line-height: 1.3;
      margin-bottom: 20px;
      color: var(--text-main);
      max-width: 900px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-lead {
      font-size: 1.15rem;
      color: var(--text-muted);
      max-width: 820px;
      margin: 0 auto 32px;
      line-height: 1.8;
    }

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

    .hero-metrics {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      margin-top: 30px;
      padding-top: 30px;
      border-top: 2px dashed #e4e4e7;
    }

    .metric-card {
      background: var(--bg-main);
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      padding: 16px;
      text-align: center;
    }

    .metric-val {
      font-size: 1.7rem;
      font-weight: 900;
      color: var(--primary-color);
      display: block;
    }

    .metric-lbl {
      font-size: 0.88rem;
      font-weight: 700;
      color: var(--text-muted);
    }

    /* 区域通用内边距 */
    .page-section {
      padding: 60px 0;
    }

    /* 模型矩阵胶囊群 */
    .model-capsules {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-item {
      padding: 8px 16px;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-pill);
      font-weight: 700;
      font-size: 0.88rem;
      box-shadow: var(--shadow-solid-sm);
      transition: all 0.2s;
    }

    .model-item:hover {
      background: var(--bg-tint-yellow);
      transform: translateY(-2px);
    }

    /* 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: 24px;
    }

    .feature-card {
      padding: 24px;
      display: flex;
      flex-direction: column;
      height: 100%;
    }

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

    .card-num {
      width: 36px;
      height: 36px;
      display: flex;
      align-items: center;
      justify-content: center;
      background: var(--accent-yellow);
      border: 2px solid var(--border-dark);
      border-radius: 8px;
      font-weight: 900;
      font-size: 1rem;
    }

    .feature-card h3 {
      font-size: 1.2rem;
      font-weight: 800;
    }

    .feature-card p {
      color: var(--text-muted);
      font-size: 0.95rem;
      line-height: 1.6;
      flex-grow: 1;
    }

    /* 步骤流程 */
    .step-list {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 18px;
      position: relative;
    }

    .step-item {
      padding: 24px 20px;
      text-align: center;
      position: relative;
    }

    .step-num-badge {
      display: inline-block;
      width: 44px;
      height: 44px;
      line-height: 40px;
      background: var(--bg-tint-blue);
      border: 2px solid var(--border-dark);
      border-radius: 50%;
      font-weight: 900;
      font-size: 1.1rem;
      margin-bottom: 14px;
    }

    .step-item h4 {
      font-size: 1.1rem;
      font-weight: 800;
      margin-bottom: 8px;
    }

    .step-item p {
      font-size: 0.9rem;
      color: var(--text-muted);
    }

    /* 对比评测卡片与表格 */
    .eval-score-banner {
      background: var(--bg-tint-yellow);
      border: 3px solid var(--border-dark);
      border-radius: var(--radius-md);
      padding: 24px;
      margin-bottom: 28px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 20px;
      box-shadow: var(--shadow-solid);
    }

    .eval-score-title {
      font-size: 1.3rem;
      font-weight: 900;
    }

    .score-pill-group {
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .score-badge {
      padding: 6px 18px;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-pill);
      font-weight: 900;
      font-size: 1.1rem;
    }

    .table-container {
      overflow-x: auto;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-solid);
    }

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

    .compare-table th, .compare-table td {
      padding: 16px 20px;
      border-bottom: 1px solid #e4e4e7;
      font-size: 0.95rem;
    }

    .compare-table th {
      background: var(--bg-tint-blue);
      font-weight: 800;
      border-bottom: 2px solid var(--border-dark);
    }

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

    .highlight-cell {
      background: #fffbeb;
      font-weight: 700;
      color: #b45309;
    }

    /* 图文与案例区 */
    .banner-media-box {
      margin-top: 30px;
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
    }

    .banner-media-item {
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-solid);
      background: #ffffff;
    }

    .banner-media-item img {
      width: 100%;
      height: 240px;
      object-fit: cover;
      display: block;
    }

    .banner-media-item p {
      padding: 12px 16px;
      font-weight: 700;
      font-size: 0.95rem;
      border-top: 2px solid var(--border-dark);
      background: #ffffff;
    }

    /* 评论卡片 */
    .testimonial-card {
      padding: 24px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      height: 100%;
    }

    .testimonial-quote {
      font-size: 0.95rem;
      color: var(--text-main);
      margin-bottom: 18px;
      font-style: italic;
    }

    .user-profile {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid #e4e4e7;
      padding-top: 14px;
    }

    .user-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--bg-tint-pink);
      border: 2px solid var(--border-dark);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 900;
    }

    .user-info h4 {
      font-size: 0.95rem;
      font-weight: 800;
    }

    .user-info span {
      font-size: 0.8rem;
      color: var(--text-muted);
    }

    /* 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: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-solid-sm);
      overflow: hidden;
    }

    .faq-header {
      padding: 18px 22px;
      font-weight: 800;
      font-size: 1.05rem;
      display: flex;
      align-items: center;
      justify-content: space-between;
      cursor: pointer;
      user-select: none;
      background: #ffffff;
      transition: background-color 0.2s;
    }

    .faq-header:hover {
      background: var(--bg-tint-yellow);
    }

    .faq-icon {
      font-size: 1.2rem;
      font-weight: 900;
      transition: transform 0.2s;
    }

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

    .faq-body {
      padding: 0 22px 18px;
      display: none;
      color: var(--text-muted);
      font-size: 0.95rem;
      line-height: 1.7;
      border-top: 1px dashed #e4e4e7;
      margin-top: 8px;
      padding-top: 14px;
    }

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

    /* 表单与联系区 */
    .form-box {
      background: #ffffff;
      border: 3px solid var(--border-dark);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-solid);
    }

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

    .form-group label {
      display: block;
      font-weight: 800;
      margin-bottom: 6px;
      font-size: 0.95rem;
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-sm);
      font-size: 0.95rem;
      background: #fafafa;
      outline: none;
      transition: border-color 0.2s, background-color 0.2s;
    }

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

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

    .contact-card-list {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .contact-info-pill {
      padding: 16px;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      background: #ffffff;
      box-shadow: var(--shadow-solid-sm);
      display: flex;
      align-items: center;
      gap: 14px;
    }

    .contact-qr-box {
      text-align: center;
      padding: 20px;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-solid-sm);
    }

    .contact-qr-box img {
      max-width: 140px;
      height: auto;
      border-radius: 8px;
      border: 1px solid #e4e4e7;
      margin-bottom: 8px;
    }

    /* 资讯与友情链接 */
    .article-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .article-link-item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 14px 18px;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-sm);
      box-shadow: var(--shadow-solid-sm);
      text-decoration: none;
      color: var(--text-main);
      font-weight: 700;
      transition: background-color 0.2s, transform 0.2s;
    }

    .article-link-item:hover {
      background: var(--bg-tint-yellow);
      transform: translateX(4px);
    }

    .links-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      padding: 20px;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-solid-sm);
    }

    .links-cloud a {
      text-decoration: none;
      color: var(--text-main);
      font-weight: 700;
      font-size: 0.9rem;
      padding: 6px 14px;
      background: var(--bg-tint-blue);
      border: 1px solid var(--border-dark);
      border-radius: var(--radius-pill);
      transition: background-color 0.2s;
    }

    .links-cloud a:hover {
      background: var(--bg-tint-pink);
    }

    /* 页脚 */
    .site-footer {
      background: #ffffff;
      border-top: 3px solid var(--border-dark);
      padding: 48px 0 24px;
      margin-top: 60px;
    }

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

    .footer-col h4 {
      font-size: 1.1rem;
      font-weight: 900;
      margin-bottom: 16px;
    }

    .footer-col p {
      color: var(--text-muted);
      font-size: 0.92rem;
      margin-bottom: 8px;
    }

    .footer-bottom {
      border-top: 1px solid #e4e4e7;
      padding-top: 20px;
      text-align: center;
      color: var(--text-muted);
      font-size: 0.88rem;
    }

    /* 悬浮工具条 */
    .floating-toolbar {
      position: fixed;
      right: 24px;
      bottom: 24px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      z-index: 99;
    }

    .floating-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #ffffff;
      border: 2px solid var(--border-dark);
      box-shadow: var(--shadow-solid);
      display: flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      color: var(--text-main);
      font-weight: 900;
      font-size: 1.2rem;
      cursor: pointer;
      transition: transform 0.2s;
    }

    .floating-btn:hover {
      transform: scale(1.1);
      background: var(--bg-tint-yellow);
    }

    /* 响应式断点 */
    @media (max-width: 992px) {
      .grid-3, .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .step-list {
        grid-template-columns: repeat(2, 1fr);
      }
      .hero-metrics {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 76px;
        left: 0;
        width: 100%;
        background: #ffffff;
        border-bottom: 2px solid var(--border-dark);
        padding: 16px 20px;
      }
      .nav-links.active {
        display: flex;
      }
      .mobile-menu-btn {
        display: block;
      }
      .hero-title {
        font-size: 1.7rem;
      }
      .grid-3, .grid-4, .grid-2 {
        grid-template-columns: 1fr;
      }
      .step-list {
        grid-template-columns: 1fr;
      }
      .banner-media-box {
        grid-template-columns: 1fr;
      }
      .hero-metrics {
        grid-template-columns: 1fr 1fr;
      }
      .floating-toolbar {
        right: 16px;
        bottom: 16px;
      }
    }