:root {
      --bg-main: #f8fafc;
      --bg-surface: #ffffff;
      --bg-card: rgba(255, 255, 255, 0.85);
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-light: #64748b;
      --color-primary: #0284c7;
      --color-primary-dark: #0369a1;
      --color-secondary: #6366f1;
      --color-accent: #ec4899;
      --border-subtle: #e2e8f0;
      --border-laser: linear-gradient(135deg, rgba(2, 132, 199, 0.4), rgba(99, 102, 241, 0.4), rgba(236, 72, 153, 0.4));
      --laser-gradient: linear-gradient(135deg, #0ea5e9 0%, #6366f1 45%, #d946ef 80%, #f59e0b 100%);
      --laser-bg-soft: linear-gradient(135deg, rgba(14, 165, 233, 0.08) 0%, rgba(99, 102, 241, 0.08) 50%, rgba(217, 70, 239, 0.08) 100%);
      --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.05);
      --shadow-md: 0 10px 25px -5px rgba(15, 23, 42, 0.08);
      --shadow-lg: 0 20px 35px -10px rgba(99, 102, 241, 0.15);
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
      --container-max: 1200px;
      --transition: all 0.28s ease;
    }

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

    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-main);
      color: var(--text-main);
      line-height: 1.65;
      overflow-x: hidden;
      position: relative;
    }

    body::before {
      content: "";
      position: fixed;
      top: 0;
      left: 0;
      width: 100vw;
      height: 100vh;
      background: 
        radial-gradient(circle at 10% 15%, rgba(14, 165, 233, 0.07) 0%, transparent 40%),
        radial-gradient(circle at 85% 30%, rgba(217, 70, 239, 0.06) 0%, transparent 45%),
        radial-gradient(circle at 50% 85%, rgba(99, 102, 241, 0.08) 0%, transparent 50%);
      z-index: -1;
      pointer-events: none;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

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

    a:hover {
      color: var(--color-primary-dark);
    }

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

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

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

    .ai-page-logo {
      height: 38px;
      width: auto;
      display: block;
      object-fit: contain;
    }

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

    .nav-links li a {
      padding: 8px 12px;
      font-size: 0.92rem;
      font-weight: 500;
      color: var(--text-muted);
      border-radius: var(--radius-sm);
      display: inline-block;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--color-primary);
      background: rgba(2, 132, 199, 0.06);
    }

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 9px 20px;
      font-size: 0.95rem;
      font-weight: 600;
      border-radius: var(--radius-sm);
      cursor: pointer;
      border: 1px solid transparent;
      transition: var(--transition);
      white-space: nowrap;
      text-decoration: none;
    }

    .btn-laser {
      background: var(--laser-gradient);
      color: #ffffff !important;
      box-shadow: 0 4px 14px rgba(99, 102, 241, 0.25);
    }

    .btn-laser:hover {
      box-shadow: 0 6px 20px rgba(217, 70, 239, 0.35);
      transform: translateY(-2px);
    }

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

    .btn-outline:hover {
      border-color: var(--color-primary);
      color: var(--color-primary);
      background: rgba(2, 132, 199, 0.04);
    }

    .nav-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      color: var(--text-main);
      cursor: pointer;
      padding: 6px;
    }

    /* 区域通用样式 */
    section {
      padding: 72px 0;
      position: relative;
    }

    .section-header {
      text-align: center;
      max-width: 780px;
      margin: 0 auto 48px;
    }

    .section-tag {
      display: inline-block;
      padding: 4px 14px;
      font-size: 0.82rem;
      font-weight: 600;
      letter-spacing: 0.5px;
      border-radius: 20px;
      background: var(--laser-bg-soft);
      border: 1px solid rgba(99, 102, 241, 0.2);
      color: var(--color-primary-dark);
      margin-bottom: 12px;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: var(--text-main);
      line-height: 1.35;
      margin-bottom: 14px;
    }

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

    /* 首屏 Hero (严格无图，纯CSS与结构) */
    .hero-section {
      padding: 80px 0 60px;
      text-align: center;
      background: linear-gradient(180deg, rgba(255, 255, 255, 0.8) 0%, rgba(241, 245, 249, 0.6) 100%);
      border-bottom: 1px solid var(--border-subtle);
      position: relative;
      overflow: hidden;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 18px;
      border-radius: 50px;
      background: #ffffff;
      border: 1px solid rgba(99, 102, 241, 0.25);
      box-shadow: var(--shadow-sm);
      font-size: 0.88rem;
      font-weight: 600;
      color: var(--color-primary-dark);
      margin-bottom: 24px;
    }

    .hero-badge span {
      display: inline-block;
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #10b981;
      box-shadow: 0 0 8px #10b981;
    }

    .hero-title {
      font-size: 2.5rem;
      font-weight: 800;
      line-height: 1.25;
      color: var(--text-main);
      max-width: 920px;
      margin: 0 auto 20px;
      letter-spacing: -0.5px;
    }

    .hero-subtitle {
      font-size: 1.15rem;
      color: var(--text-muted);
      max-width: 760px;
      margin: 0 auto 32px;
      line-height: 1.65;
    }

    .hero-actions {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }

    .hero-btn-main {
      padding: 14px 34px;
      font-size: 1.05rem;
      border-radius: var(--radius-sm);
    }

    .hero-stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      max-width: 960px;
      margin: 0 auto;
    }

    .stat-card {
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      padding: 24px 16px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      position: relative;
      overflow: hidden;
    }

    .stat-card::after {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 3px;
      background: var(--laser-gradient);
    }

    .stat-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }

    .stat-value {
      font-size: 1.75rem;
      font-weight: 800;
      color: var(--color-primary-dark);
      margin-bottom: 4px;
    }

    .stat-label {
      font-size: 0.88rem;
      color: var(--text-light);
    }

    /* 平台矩阵卡片 */
    .model-tags-wrapper {
      margin-top: 48px;
      padding: 24px;
      background: #ffffff;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-sm);
      text-align: left;
    }

    .model-tags-title {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

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

    .model-tag-item {
      padding: 4px 10px;
      background: var(--bg-main);
      border: 1px solid var(--border-subtle);
      border-radius: 6px;
      font-size: 0.82rem;
      color: var(--text-muted);
      font-weight: 500;
      transition: var(--transition);
    }

    .model-tag-item:hover {
      border-color: var(--color-secondary);
      color: var(--color-secondary);
      background: #ffffff;
    }

    /* 服务能力卡片 */
    .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;
    }

    .card {
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      position: relative;
      display: flex;
      flex-direction: column;
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: rgba(99, 102, 241, 0.3);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: 12px;
      background: var(--laser-bg-soft);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.4rem;
      color: var(--color-primary-dark);
      margin-bottom: 18px;
    }

    .card-title {
      font-size: 1.18rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }

    .card-text {
      font-size: 0.92rem;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }

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

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

    .step-num {
      width: 32px;
      height: 32px;
      border-radius: 50%;
      background: var(--laser-gradient);
      color: #ffffff;
      font-weight: 700;
      font-size: 0.95rem;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 14px;
    }

    .step-box h3 {
      font-size: 1.05rem;
      font-weight: 700;
      margin-bottom: 8px;
    }

    .step-box p {
      font-size: 0.88rem;
      color: var(--text-muted);
    }

    /* 素材图片区域 (非首屏) */
    .media-card-box {
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

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

    .media-card-img-wrap img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
      transition: var(--transition);
    }

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

    .media-card-content {
      padding: 20px;
    }

    /* 对比评测表格与卡片 */
    .compare-section-card {
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-md);
    }

    .rating-banner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 20px;
      padding: 24px;
      background: var(--laser-bg-soft);
      border-radius: var(--radius-md);
      border: 1px solid rgba(99, 102, 241, 0.25);
      margin-bottom: 32px;
    }

    .rating-score-group {
      display: flex;
      align-items: baseline;
      gap: 12px;
    }

    .rating-big-num {
      font-size: 3rem;
      font-weight: 900;
      color: var(--color-primary-dark);
      line-height: 1;
    }

    .rating-max {
      font-size: 1.15rem;
      color: var(--text-light);
    }

    .rating-stars {
      color: #f59e0b;
      font-size: 1.25rem;
      font-weight: 700;
    }

    .table-container {
      width: 100%;
      overflow-x: auto;
      margin-top: 16px;
    }

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

    .compare-table th,
    .compare-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-subtle);
      font-size: 0.95rem;
    }

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

    .compare-table tr:hover td {
      background: rgba(2, 132, 199, 0.02);
    }

    .compare-table td.highlight {
      color: var(--color-primary-dark);
      font-weight: 700;
      background: rgba(2, 132, 199, 0.04);
    }

    /* 用户评论 */
    .review-author {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 16px;
      padding-top: 16px;
      border-top: 1px solid var(--border-subtle);
    }

    .review-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--laser-gradient);
      display: flex;
      align-items: center;
      justify-content: center;
      color: #ffffff;
      font-weight: 700;
      font-size: 1rem;
    }

    .review-name {
      font-size: 0.95rem;
      font-weight: 700;
      color: var(--text-main);
    }

    .review-role {
      font-size: 0.82rem;
      color: var(--text-light);
    }

    /* FAQ 手风琴 */
    .faq-list {
      max-width: 880px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      overflow: hidden;
      transition: var(--transition);
    }

    .faq-item:hover {
      border-color: rgba(99, 102, 241, 0.3);
    }

    .faq-question {
      padding: 20px 24px;
      width: 100%;
      text-align: left;
      background: none;
      border: none;
      font-size: 1.05rem;
      font-weight: 600;
      color: var(--text-main);
      display: flex;
      align-items: center;
      justify-content: space-between;
      cursor: pointer;
    }

    .faq-icon {
      font-size: 1.25rem;
      transition: transform 0.25s ease;
      color: var(--color-primary);
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      padding: 0 24px;
      background: #fafbfc;
      font-size: 0.94rem;
      color: var(--text-muted);
      line-height: 1.7;
    }

    .faq-item.active .faq-answer {
      max-height: 300px;
      padding: 0 24px 20px;
    }

    /* 表单区域 */
    .form-box {
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-md);
      max-width: 640px;
      margin: 0 auto;
    }

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

    .form-label {
      display: block;
      font-size: 0.92rem;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-sm);
      font-size: 0.95rem;
      color: var(--text-main);
      background: #ffffff;
      transition: var(--transition);
      outline: none;
      font-family: inherit;
    }

    .form-control:focus {
      border-color: var(--color-primary);
      box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.15);
    }

    textarea.form-control {
      min-height: 110px;
      resize: vertical;
    }

    /* 文章列表与外链展示 */
    .article-links-box {
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      padding: 24px;
      margin-top: 32px;
    }

    .article-links-title {
      font-size: 1rem;
      font-weight: 700;
      margin-bottom: 14px;
      color: var(--text-main);
    }

    .article-url-list {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      list-style: none;
    }

    .article-url-list a {
      font-size: 0.88rem;
      padding: 6px 14px;
      background: var(--bg-main);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-sm);
      color: var(--text-muted);
      display: inline-block;
    }

    .article-url-list a:hover {
      border-color: var(--color-primary);
      color: var(--color-primary);
    }

    /* 底部通用区域 */
    .site-footer {
      background: #ffffff;
      border-top: 1px solid var(--border-subtle);
      padding: 56px 0 28px;
      margin-top: 48px;
      color: var(--text-muted);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.2fr 1.2fr;
      gap: 36px;
      margin-bottom: 40px;
    }

    .footer-brand p {
      font-size: 0.92rem;
      margin-top: 14px;
      max-width: 320px;
      line-height: 1.6;
    }

    .footer-heading {
      font-size: 1rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 18px;
    }

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

    .footer-links-col a {
      color: var(--text-muted);
      font-size: 0.9rem;
    }

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

    .qr-container {
      display: flex;
      flex-direction: column;
      align-items: flex-start;
      gap: 8px;
    }

    .qr-container img {
      width: 110px;
      height: 110px;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-sm);
      padding: 4px;
      background: #ffffff;
    }

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

    .friend-links-title {
      font-size: 0.88rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }

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

    .friend-links-list a {
      font-size: 0.85rem;
      color: var(--text-light);
    }

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

    .footer-bottom {
      padding-top: 20px;
      border-top: 1px solid var(--border-subtle);
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 12px;
      font-size: 0.85rem;
      color: var(--text-light);
    }

    /* 悬浮客服与返回顶部 */
    .floating-toolbar {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 99;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .floating-btn {
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: #ffffff;
      border: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-md);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.15rem;
      color: var(--text-main);
      cursor: pointer;
      transition: var(--transition);
      text-decoration: none;
      position: relative;
    }

    .floating-btn:hover {
      background: var(--color-primary);
      color: #ffffff;
      border-color: var(--color-primary);
    }

    .floating-qr-pop {
      display: none;
      position: absolute;
      right: 56px;
      bottom: 0;
      background: #ffffff;
      padding: 12px;
      border-radius: var(--radius-sm);
      box-shadow: var(--shadow-lg);
      border: 1px solid var(--border-subtle);
      width: 140px;
      text-align: center;
    }

    .floating-qr-pop img {
      width: 100%;
      height: auto;
      display: block;
    }

    .floating-qr-pop span {
      display: block;
      font-size: 0.75rem;
      color: var(--text-muted);
      margin-top: 6px;
    }

    .floating-btn:hover .floating-qr-pop {
      display: block;
    }

    /* 移动端响应式 */
    @media (max-width: 992px) {
      .grid-4, .hero-stats-grid, .workflow-steps {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        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: 16px 24px;
        border-bottom: 1px solid var(--border-subtle);
        box-shadow: var(--shadow-md);
      }
      .nav-links.active {
        display: flex;
      }
      .nav-toggle {
        display: block;
      }
      .hero-title {
        font-size: 1.85rem;
      }
      .grid-4, .grid-3, .grid-2, .hero-stats-grid, .workflow-steps {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .rating-banner {
        flex-direction: column;
        align-items: flex-start;
      }
    }