:root {
      --primary: #0f52ba;
      --primary-hover: #0d459d;
      --primary-light: #e8f1fd;
      --secondary: #00a4e4;
      --accent: #ff6b35;
      --text-main: #1e293b;
      --text-muted: #475569;
      --text-light: #64748b;
      --bg-page: #f8faff;
      --bg-card: #ffffff;
      --bg-alt: #f0f5fc;
      --border-color: #dbeafe;
      --border-subtle: #e2e8f0;
      --shadow-sm: 0 2px 6px rgba(15, 82, 186, 0.05);
      --shadow-md: 0 6px 18px rgba(15, 82, 186, 0.08);
      --shadow-lg: 0 12px 30px rgba(15, 82, 186, 0.12);
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 16px;
      --radius-full: 9999px;
      --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-page);
      color: var(--text-main);
      line-height: 1.65;
      overflow-x: hidden;
      min-width: 320px;
    }

    /* 统一全局容器 */
    .container {
      width: 100%;
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }

    /* 导航栏 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.96);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

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

    .brand-area {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
    }

    .ai-page-logo {
      height: 42px;
      width: auto;
      display: block;
    }

    .brand-title-group {
      display: flex;
      flex-direction: column;
    }

    .brand-name {
      font-size: 1.25rem;
      font-weight: 800;
      color: var(--primary);
      letter-spacing: -0.5px;
      line-height: 1.2;
    }

    .brand-desc {
      font-size: 0.72rem;
      color: var(--text-muted);
      font-weight: 500;
    }

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

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

    .nav-links a {
      display: block;
      padding: 8px 14px;
      color: var(--text-main);
      font-size: 0.95rem;
      font-weight: 500;
      text-decoration: none;
      border-radius: var(--radius-sm);
      transition: var(--transition);
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      background-color: var(--primary-light);
    }

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 22px;
      font-size: 0.95rem;
      font-weight: 600;
      text-decoration: none;
      border-radius: var(--radius-md);
      transition: var(--transition);
      cursor: pointer;
      border: 1px solid transparent;
      white-space: nowrap;
    }

    .btn-primary {
      background-color: var(--primary);
      color: #ffffff;
      box-shadow: 0 4px 12px rgba(15, 82, 186, 0.25);
    }

    .btn-primary:hover {
      background-color: var(--primary-hover);
      transform: translateY(-2px);
      box-shadow: 0 6px 16px rgba(15, 82, 186, 0.35);
      color: #ffffff;
    }

    .btn-outline {
      background-color: transparent;
      border-color: var(--primary);
      color: var(--primary);
    }

    .btn-outline:hover {
      background-color: var(--primary-light);
      transform: translateY(-2px);
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      cursor: pointer;
      padding: 6px;
      color: var(--text-main);
    }

    /* Section 通用规范 */
    .section-wrap {
      padding: 72px 0;
      position: relative;
    }

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

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

    .section-badge {
      display: inline-block;
      padding: 4px 14px;
      background: var(--primary-light);
      color: var(--primary);
      font-size: 0.82rem;
      font-weight: 700;
      border-radius: var(--radius-full);
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 14px;
      line-height: 1.3;
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* 首屏 Hero 区域 (严格无图片) */
    .hero-section {
      padding: 80px 0 68px;
      background: radial-gradient(circle at 50% 10%, rgba(219, 234, 254, 0.7) 0%, rgba(248, 250, 255, 1) 70%);
      border-bottom: 1px solid var(--border-color);
      position: relative;
      text-align: center;
    }

    .hero-inner {
      max-width: 880px;
      margin: 0 auto;
    }

    .hero-tag {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 16px;
      background-color: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-full);
      color: var(--primary);
      font-size: 0.88rem;
      font-weight: 600;
      margin-bottom: 24px;
      box-shadow: var(--shadow-sm);
    }

    .hero-tag-dot {
      width: 8px;
      height: 8px;
      background-color: var(--accent);
      border-radius: 50%;
      display: inline-block;
      animation: pulseDot 2s infinite ease-in-out;
    }

    @keyframes pulseDot {
      0%, 100% { transform: scale(1); opacity: 1; }
      50% { transform: scale(1.4); opacity: 0.6; }
    }

    .hero-title {
      font-size: 2.75rem;
      font-weight: 850;
      color: #0b2545;
      line-height: 1.25;
      margin-bottom: 22px;
      letter-spacing: -0.5px;
    }

    .hero-title span {
      color: var(--primary);
      position: relative;
    }

    .hero-subtitle {
      font-size: 1.18rem;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 36px;
      max-width: 760px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-cta-group {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 16px;
      margin-bottom: 50px;
      flex-wrap: wrap;
    }

    .btn-hero-main {
      padding: 14px 34px;
      font-size: 1.1rem;
      background: linear-gradient(135deg, var(--primary) 0%, #1e40af 100%);
      color: #ffffff;
      border-radius: var(--radius-md);
      box-shadow: 0 8px 24px rgba(15, 82, 186, 0.3);
      font-weight: 700;
    }

    .btn-hero-main:hover {
      transform: translateY(-3px);
      box-shadow: 0 12px 28px rgba(15, 82, 186, 0.4);
      color: #ffffff;
    }

    .btn-hero-sub {
      padding: 14px 28px;
      font-size: 1.05rem;
      background: #ffffff;
      color: var(--text-main);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
    }

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

    /* 首屏数据指标卡片 */
    .hero-metrics {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      max-width: 1000px;
      margin: 0 auto;
    }

    .metric-card {
      background: #ffffff;
      padding: 22px 18px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: var(--transition);
    }

    .metric-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: var(--secondary);
    }

    .metric-num {
      font-size: 1.9rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 6px;
      display: block;
    }

    .metric-label {
      font-size: 0.88rem;
      color: var(--text-muted);
      font-weight: 500;
    }

    /* 标签云 (模型支持矩阵) */
    .models-chip-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-chip {
      background: #ffffff;
      border: 1px solid var(--border-color);
      padding: 6px 14px;
      border-radius: var(--radius-full);
      font-size: 0.85rem;
      color: var(--text-muted);
      font-weight: 600;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }

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

    /* 卡片网格布局 */
    .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: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      height: 100%;
    }

    .feature-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
      border-color: #93c5fd;
    }

    .feature-icon-box {
      width: 48px;
      height: 48px;
      border-radius: var(--radius-md);
      background-color: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.35rem;
      margin-bottom: 20px;
      font-weight: 700;
    }

    .feature-card h3 {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
      line-height: 1.4;
    }

    .feature-card p {
      font-size: 0.94rem;
      color: var(--text-muted);
      line-height: 1.65;
      flex-grow: 1;
    }

    .feature-card .card-meta {
      margin-top: 18px;
      padding-top: 14px;
      border-top: 1px dashed var(--border-color);
      font-size: 0.82rem;
      color: var(--primary);
      font-weight: 600;
    }

    /* 标准流程时间线 */
    .timeline-steps {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

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

    .step-item:hover {
      border-color: var(--primary);
      box-shadow: var(--shadow-md);
    }

    .step-num {
      width: 38px;
      height: 38px;
      border-radius: 50%;
      background: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1rem;
      margin-bottom: 16px;
    }

    .step-item h4 {
      font-size: 1.15rem;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--text-main);
    }

    .step-item p {
      font-size: 0.88rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* 对比评测表格与评级组件 */
    .eval-highlight {
      background: #ffffff;
      border: 2px solid var(--primary);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-md);
      margin-bottom: 36px;
    }

    .eval-score-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 20px;
      padding-bottom: 24px;
      border-bottom: 1px solid var(--border-color);
      margin-bottom: 28px;
    }

    .eval-score-main {
      display: flex;
      align-items: baseline;
      gap: 14px;
    }

    .eval-score-val {
      font-size: 3.5rem;
      font-weight: 900;
      color: var(--primary);
      line-height: 1;
    }

    .eval-score-max {
      font-size: 1.25rem;
      color: var(--text-muted);
      font-weight: 600;
    }

    .eval-star-rating {
      font-size: 1.4rem;
      color: #f59e0b;
      margin-left: 8px;
    }

    .eval-badges {
      display: flex;
      gap: 10px;
      flex-wrap: wrap;
    }

    .badge-pill {
      background: var(--primary-light);
      color: var(--primary);
      padding: 6px 14px;
      border-radius: var(--radius-full);
      font-size: 0.85rem;
      font-weight: 700;
    }

    .table-container {
      width: 100%;
      overflow-x: auto;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
    }

    .custom-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.94rem;
      min-width: 680px;
      background: #ffffff;
    }

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

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

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

    .col-highlight {
      background-color: rgba(232, 241, 253, 0.45);
      font-weight: 600;
      color: var(--primary);
    }

    /* 案例中心图文卡片 */
    .case-media-card {
      background: #ffffff;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }

    .case-media-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
    }

    .case-image-holder {
      width: 100%;
      position: relative;
      background: #e2e8f0;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
    }

    .case-image-holder img {
      width: 100%;
      max-width: 100%;
      height: auto;
      display: block;
      transition: var(--transition);
    }

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

    .case-body {
      padding: 22px;
      flex-grow: 1;
      display: flex;
      flex-direction: column;
    }

    .case-tag {
      font-size: 0.78rem;
      color: var(--primary);
      font-weight: 700;
      text-transform: uppercase;
      margin-bottom: 8px;
    }

    .case-title {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .case-text {
      font-size: 0.88rem;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }

    /* 用户评论评价卡片 */
    .review-card {
      background: #ffffff;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }

    .review-card:hover {
      border-color: var(--primary);
      box-shadow: var(--shadow-md);
    }

    .review-stars {
      color: #f59e0b;
      font-size: 1rem;
      margin-bottom: 14px;
    }

    .review-content {
      font-size: 0.92rem;
      color: var(--text-main);
      line-height: 1.65;
      margin-bottom: 20px;
      flex-grow: 1;
      font-style: italic;
    }

    .review-author {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid var(--border-subtle);
      padding-top: 14px;
    }

    .review-avatar-char {
      width: 42px;
      height: 42px;
      border-radius: 50%;
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1rem;
    }

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

    .review-info-role {
      font-size: 0.8rem;
      color: var(--text-light);
    }

    /* FAQ 折叠面板 */
    .faq-list {
      max-width: 860px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

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

    .faq-item:hover {
      border-color: #93c5fd;
    }

    .faq-question {
      padding: 18px 22px;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
      font-size: 1.05rem;
      font-weight: 600;
      color: var(--text-main);
      user-select: none;
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background-color: #fafcff;
      border-top: 1px solid transparent;
      padding: 0 22px;
      font-size: 0.92rem;
      color: var(--text-muted);
      line-height: 1.7;
    }

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

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

    .faq-item.active .faq-answer {
      max-height: 220px;
      padding: 18px 22px;
      border-top-color: var(--border-color);
    }

    /* 表单与需求匹配 */
    .form-box-wrapper {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 40px;
      box-shadow: var(--shadow-md);
    }

    .custom-form {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
    }

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

    .form-group.full-width {
      grid-column: 1 / -1;
    }

    .form-label {
      font-size: 0.88rem;
      font-weight: 600;
      color: var(--text-main);
    }

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

    .form-control:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(15, 82, 186, 0.15);
    }

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

    /* 文章与资讯 */
    .article-link-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
    }

    .article-item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
      padding: 10px 14px;
      border-radius: var(--radius-sm);
      text-decoration: none;
      color: var(--text-main);
      border-bottom: 1px dashed var(--border-subtle);
      transition: var(--transition);
    }

    .article-item:last-child {
      border-bottom: none;
    }

    .article-item:hover {
      background-color: var(--primary-light);
      color: var(--primary);
      transform: translateX(4px);
    }

    .article-item-title {
      font-size: 0.95rem;
      font-weight: 600;
    }

    .article-item-url {
      font-size: 0.8rem;
      color: var(--text-light);
    }

    /* 友情链接 */
    .friend-links-bar {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      align-items: center;
      padding: 16px 20px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
    }

    .friend-links-bar a {
      color: var(--text-muted);
      text-decoration: none;
      font-size: 0.88rem;
      padding: 4px 10px;
      border-radius: var(--radius-sm);
      background: var(--bg-alt);
      transition: var(--transition);
    }

    .friend-links-bar a:hover {
      background: var(--primary-light);
      color: var(--primary);
    }

    /* 页脚 */
    .site-footer {
      background-color: #0b1f3a;
      color: #cbd5e1;
      padding: 56px 0 24px;
      border-top: 1px solid #1e3a5f;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 36px;
      margin-bottom: 40px;
    }

    .footer-brand h3 {
      color: #ffffff;
      font-size: 1.35rem;
      margin-bottom: 12px;
      font-weight: 700;
    }

    .footer-brand p {
      font-size: 0.88rem;
      line-height: 1.65;
      color: #94a3b8;
      margin-bottom: 16px;
    }

    .footer-title {
      color: #ffffff;
      font-size: 1.05rem;
      font-weight: 700;
      margin-bottom: 16px;
    }

    .footer-links-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .footer-links-list a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.88rem;
      transition: var(--transition);
    }

    .footer-links-list a:hover {
      color: #ffffff;
      padding-left: 4px;
    }

    .contact-item {
      font-size: 0.88rem;
      color: #94a3b8;
      margin-bottom: 8px;
    }

    .qr-holder {
      margin-top: 12px;
    }

    .qr-holder img {
      max-width: 110px;
      height: auto;
      border-radius: var(--radius-sm);
      border: 2px solid rgba(255, 255, 255, 0.1);
      display: block;
    }

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

    .ai-page-home-link {
      color: var(--primary);
      text-decoration: none;
      font-weight: 600;
    }

    /* 浮动操作栏与回到顶部 */
    .float-dock {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 46px;
      height: 46px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      box-shadow: var(--shadow-md);
      cursor: pointer;
      text-decoration: none;
      transition: var(--transition);
      font-size: 1.1rem;
    }

    .float-btn:hover {
      background: var(--primary);
      color: #ffffff;
      transform: scale(1.08);
    }

    /* 响应式样式 */
    @media (max-width: 1024px) {
      .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .timeline-steps {
        grid-template-columns: repeat(2, 1fr);
      }
      .hero-metrics {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .hero-title {
        font-size: 2rem;
      }
      .section-title {
        font-size: 1.6rem;
      }
      .grid-3,
      .grid-2 {
        grid-template-columns: 1fr;
      }
      .hero-metrics {
        grid-template-columns: 1fr;
      }
      .custom-form {
        grid-template-columns: 1fr;
      }
      .mobile-menu-btn {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 16px 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.show {
        display: flex;
      }
      .nav-links a {
        padding: 10px 14px;
        width: 100%;
      }
      .nav-action {
        display: none;
      }
      .footer-grid {
        grid-template-columns: 1fr;
        gap: 28px;
      }
    }