:root {
      --primary: #2563eb;
      --primary-gradient: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
      --accent-pop: #ff007a;
      --accent-cyan: #00d2ff;
      --accent-amber: #f59e0b;
      --accent-emerald: #10b981;
      --bg-base: #f8fafc;
      --bg-surface: #ffffff;
      --bg-card: #ffffff;
      --text-main: #0f172a;
      --text-sub: #475569;
      --text-muted: #64748b;
      --border-light: #e2e8f0;
      --border-highlight: #c7d2fe;
      --shadow-sm: 0 2px 8px rgba(37, 99, 235, 0.06);
      --shadow-md: 0 10px 25px -5px rgba(37, 99, 235, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
      --shadow-lg: 0 20px 35px -10px rgba(124, 58, 237, 0.15);
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 22px;
      --max-width: 1200px;
      --transition-base: 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, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-base);
      color: var(--text-main);
      line-height: 1.6;
      background-image: 
        radial-gradient(at 0% 0%, rgba(37, 99, 235, 0.07) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(255, 0, 122, 0.05) 0px, transparent 50%),
        radial-gradient(at 50% 50%, rgba(0, 210, 255, 0.04) 0px, transparent 60%);
      background-attachment: fixed;
      overflow-x: hidden;
    }

    a {
      color: inherit;
      text-decoration: none;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    .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, 0.94);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
    }

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

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

    .ai-page-logo {
      height: 42px;
      width: auto;
      object-fit: contain;
    }

    .brand-title {
      font-size: 1.25rem;
      font-weight: 800;
      color: var(--text-main);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .brand-badge {
      background: linear-gradient(135deg, var(--accent-pop), #7c3aed);
      color: #ffffff;
      font-size: 0.7rem;
      font-weight: 700;
      padding: 2px 6px;
      border-radius: 4px;
      text-transform: uppercase;
    }

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

    .nav-item a {
      font-size: 0.92rem;
      font-weight: 600;
      color: var(--text-sub);
      padding: 10px 14px;
      border-radius: var(--radius-sm);
      transition: var(--transition-base);
    }

    .nav-item a:hover {
      color: var(--primary);
      background: rgba(37, 99, 235, 0.08);
    }

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

    .btn-portal {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: var(--primary-gradient);
      color: #ffffff !important;
      font-weight: 700;
      font-size: 0.88rem;
      padding: 9px 18px;
      border-radius: 30px;
      box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
      transition: var(--transition-base);
      border: none;
      cursor: pointer;
    }

    .btn-portal:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 18px rgba(37, 99, 235, 0.4);
    }

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

    /* Hero 首屏 - 纯色/渐变/几何/科技质感，禁止任何图片 */
    .hero-section {
      padding: 70px 0 60px;
      position: relative;
      overflow: hidden;
      background: linear-gradient(180deg, rgba(255, 255, 255, 0.8) 0%, rgba(241, 245, 249, 0.6) 100%);
      border-bottom: 1px solid var(--border-light);
    }

    .hero-content {
      text-align: center;
      max-width: 900px;
      margin: 0 auto;
      position: relative;
      z-index: 2;
    }

    .hero-tag {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: rgba(37, 99, 235, 0.08);
      color: var(--primary);
      border: 1px solid rgba(37, 99, 235, 0.2);
      padding: 6px 16px;
      border-radius: 50px;
      font-size: 0.85rem;
      font-weight: 700;
      margin-bottom: 20px;
    }

    .hero-tag span.badge-dot {
      width: 8px;
      height: 8px;
      background-color: var(--accent-pop);
      border-radius: 50%;
      box-shadow: 0 0 10px var(--accent-pop);
    }

    .hero-h1 {
      font-size: 2.8rem;
      font-weight: 900;
      line-height: 1.25;
      color: var(--text-main);
      letter-spacing: -0.5px;
      margin-bottom: 20px;
    }

    .hero-h1 .text-glow {
      color: var(--primary);
      position: relative;
      display: inline-block;
    }

    .hero-desc {
      font-size: 1.12rem;
      color: var(--text-sub);
      line-height: 1.7;
      margin-bottom: 34px;
      max-width: 780px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-btn-group {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 45px;
    }

    .btn-main-action {
      background: linear-gradient(135deg, #2563eb 0%, #d946ef 100%);
      color: #ffffff !important;
      font-size: 1.05rem;
      font-weight: 800;
      padding: 14px 34px;
      border-radius: 40px;
      box-shadow: 0 8px 22px rgba(217, 70, 239, 0.35);
      transition: var(--transition-base);
    }

    .btn-main-action:hover {
      transform: translateY(-3px) scale(1.02);
      box-shadow: 0 12px 28px rgba(37, 99, 235, 0.4);
    }

    .btn-secondary-action {
      background: #ffffff;
      color: var(--text-main);
      font-size: 1.02rem;
      font-weight: 700;
      padding: 13px 28px;
      border-radius: 40px;
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
      transition: var(--transition-base);
    }

    .btn-secondary-action:hover {
      background: #f1f5f9;
      border-color: var(--primary);
      color: var(--primary);
    }

    .hero-metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 18px;
      margin-top: 15px;
    }

    .metric-card {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 20px 15px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      position: relative;
      overflow: hidden;
      transition: var(--transition-base);
    }

    .metric-card::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 3px;
      background: var(--primary-gradient);
    }

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

    .metric-val {
      font-size: 1.9rem;
      font-weight: 900;
      color: var(--text-main);
      line-height: 1;
      margin-bottom: 6px;
    }

    .metric-val span {
      color: var(--accent-pop);
      font-size: 1.2rem;
    }

    .metric-lbl {
      font-size: 0.82rem;
      color: var(--text-muted);
      font-weight: 600;
    }

    /* Section 通用规范 */
    .section-wrap {
      padding: 70px 0;
      border-bottom: 1px solid rgba(226, 232, 240, 0.7);
    }

    .section-head {
      text-align: center;
      margin-bottom: 45px;
    }

    .section-tag {
      font-size: 0.8rem;
      font-weight: 800;
      letter-spacing: 1px;
      color: var(--primary);
      text-transform: uppercase;
      display: inline-block;
      margin-bottom: 8px;
      background: rgba(37, 99, 235, 0.08);
      padding: 4px 12px;
      border-radius: 30px;
    }

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

    .section-subtitle {
      font-size: 1rem;
      color: var(--text-sub);
      max-width: 650px;
      margin: 0 auto;
    }

    /* 模型矩阵与标签云 */
    .model-pills-wrap {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 10px;
      margin-top: 25px;
    }

    .model-pill {
      background: #ffffff;
      border: 1px solid var(--border-light);
      padding: 8px 16px;
      border-radius: 30px;
      font-size: 0.86rem;
      font-weight: 700;
      color: var(--text-sub);
      box-shadow: 0 2px 4px rgba(0, 0, 0, 0.03);
      display: flex;
      align-items: center;
      gap: 6px;
      transition: var(--transition-base);
    }

    .model-pill:hover {
      background: #eff6ff;
      border-color: var(--primary);
      color: var(--primary);
      transform: translateY(-2px);
    }

    .model-pill .dot {
      width: 6px;
      height: 6px;
      border-radius: 50%;
      background-color: var(--accent-emerald);
    }

    /* 场景卡片网格 */
    .grid-scenarios {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 22px;
    }

    .scene-card {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      transition: var(--transition-base);
      position: relative;
    }

    .scene-card:hover {
      border-color: var(--border-highlight);
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
    }

    .scene-icon-box {
      width: 44px;
      height: 44px;
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.25rem;
      font-weight: 800;
      color: #ffffff;
      background: var(--primary-gradient);
      margin-bottom: 16px;
    }

    .scene-card:nth-child(2n) .scene-icon-box {
      background: linear-gradient(135deg, var(--accent-pop), #f59e0b);
    }

    .scene-card:nth-child(3n) .scene-icon-box {
      background: linear-gradient(135deg, #06b6d4, #3b82f6);
    }

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

    .scene-desc {
      font-size: 0.9rem;
      color: var(--text-sub);
      line-height: 1.6;
      margin-bottom: 14px;
      flex-grow: 1;
    }

    .scene-tag-list {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
    }

    .scene-badge {
      font-size: 0.75rem;
      padding: 2px 8px;
      border-radius: 4px;
      background: #f1f5f9;
      color: var(--text-sub);
      font-weight: 600;
    }

    /* 评测区域 (高亮艳彩卡片) */
    .review-score-banner {
      background: linear-gradient(135deg, #1e1b4b 0%, #312e81 50%, #4338ca 100%);
      border-radius: var(--radius-lg);
      padding: 40px;
      color: #ffffff;
      box-shadow: var(--shadow-lg);
      margin-bottom: 30px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 25px;
    }

    .score-left h3 {
      font-size: 1.7rem;
      font-weight: 800;
      margin-bottom: 8px;
      color: #ffffff;
    }

    .score-left p {
      color: #c7d2fe;
      font-size: 0.95rem;
      max-width: 520px;
    }

    .score-right {
      display: flex;
      align-items: center;
      gap: 20px;
      background: rgba(255, 255, 255, 0.1);
      padding: 16px 24px;
      border-radius: var(--radius-md);
      backdrop-filter: blur(8px);
      border: 1px solid rgba(255, 255, 255, 0.2);
    }

    .score-big {
      font-size: 3.2rem;
      font-weight: 900;
      color: #fde047;
      line-height: 1;
    }

    .score-meta {
      display: flex;
      flex-direction: column;
    }

    .score-stars {
      color: #fde047;
      font-size: 1.2rem;
      letter-spacing: 2px;
    }

    .score-caption {
      font-size: 0.85rem;
      color: #ffffff;
      font-weight: 600;
    }

    /* 对比表格 */
    .compare-table-wrap {
      background: #ffffff;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
      overflow-x: auto;
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      min-width: 700px;
      text-align: left;
    }

    .compare-table th, .compare-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-light);
      font-size: 0.92rem;
    }

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

    .compare-table tr:hover td {
      background: #fcfaff;
    }

    .compare-table .highlight-col {
      background: rgba(37, 99, 235, 0.03);
      font-weight: 700;
      color: var(--primary);
    }

    .tag-check {
      display: inline-flex;
      align-items: center;
      gap: 4px;
      color: var(--accent-emerald);
      font-weight: 700;
    }

    /* 图文媒体展示 */
    .media-card-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      margin-top: 30px;
    }

    .media-frame {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .media-frame img {
      width: 100%;
      height: 260px;
      object-fit: cover;
    }

    .media-caption {
      padding: 16px;
    }

    .media-caption h4 {
      font-size: 1.05rem;
      color: var(--text-main);
      margin-bottom: 6px;
    }

    .media-caption p {
      font-size: 0.86rem;
      color: var(--text-muted);
    }

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

    .step-card {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 22px;
      position: relative;
      box-shadow: var(--shadow-sm);
    }

    .step-num {
      width: 32px;
      height: 32px;
      border-radius: 50%;
      background: var(--primary);
      color: #ffffff;
      font-weight: 800;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 0.9rem;
      margin-bottom: 12px;
    }

    .step-title {
      font-size: 1.05rem;
      font-weight: 700;
      margin-bottom: 6px;
    }

    .step-desc {
      font-size: 0.85rem;
      color: var(--text-sub);
    }

    /* 客户评价网格 */
    .review-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
    }

    .review-card {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .review-text {
      font-size: 0.92rem;
      color: var(--text-sub);
      line-height: 1.65;
      margin-bottom: 16px;
    }

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

    .author-avatar {
      width: 40px;
      height: 40px;
      border-radius: 50%;
      background: var(--primary-gradient);
      color: #ffffff;
      font-weight: 800;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 0.9rem;
    }

    .author-info h4 {
      font-size: 0.92rem;
      font-weight: 700;
      color: var(--text-main);
    }

    .author-info p {
      font-size: 0.78rem;
      color: var(--text-muted);
    }

    /* 表单与需求匹配 */
    .form-box {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-md);
      max-width: 800px;
      margin: 0 auto;
    }

    .form-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 18px;
    }

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

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

    .form-label {
      font-size: 0.88rem;
      font-weight: 700;
      color: var(--text-main);
    }

    .form-input, .form-select, .form-textarea {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-sm);
      font-size: 0.92rem;
      background: #fdfdfd;
      color: var(--text-main);
      outline: none;
      transition: var(--transition-base);
    }

    .form-input:focus, .form-select:focus, .form-textarea:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
      background: #ffffff;
    }

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

    .btn-submit {
      grid-column: span 2;
      background: var(--primary-gradient);
      color: #ffffff;
      font-size: 1rem;
      font-weight: 700;
      padding: 14px;
      border: none;
      border-radius: var(--radius-sm);
      cursor: pointer;
      box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
      transition: var(--transition-base);
    }

    .btn-submit:hover {
      opacity: 0.95;
      transform: translateY(-2px);
    }

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

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

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

    .faq-question:hover {
      color: var(--primary);
      background: #f8fafc;
    }

    .faq-icon {
      font-size: 1.2rem;
      transition: transform 0.28s ease;
      color: var(--text-muted);
    }

    .faq-answer {
      display: none;
      padding: 0 22px 18px;
      font-size: 0.92rem;
      color: var(--text-sub);
      line-height: 1.65;
      border-top: 1px solid #f1f5f9;
      margin-top: 4px;
      padding-top: 14px;
    }

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

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

    /* 资讯与百科 */
    .article-links-box {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-sm);
    }

    .article-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .article-item a {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 10px 14px;
      border-radius: var(--radius-sm);
      font-size: 0.92rem;
      color: var(--text-sub);
      background: #f8fafc;
      transition: var(--transition-base);
    }

    .article-item a:hover {
      background: #eff6ff;
      color: var(--primary);
      padding-left: 18px;
    }

    /* 联系与社群专区 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }

    .contact-card {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-sm);
    }

    .contact-card h4 {
      font-size: 1.15rem;
      margin-bottom: 14px;
      color: var(--text-main);
    }

    .contact-meta-item {
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 10px;
      font-size: 0.92rem;
      color: var(--text-sub);
    }

    .contact-meta-item strong {
      color: var(--text-main);
      min-width: 80px;
    }

    .qr-container {
      display: flex;
      align-items: center;
      gap: 20px;
      margin-top: 15px;
      padding: 15px;
      background: #f8fafc;
      border-radius: var(--radius-sm);
    }

    .qr-container img {
      width: 110px;
      height: 110px;
      border-radius: 6px;
      border: 1px solid var(--border-light);
      background: #ffffff;
    }

    /* 页脚 */
    .site-footer {
      background: #ffffff;
      border-top: 1px solid var(--border-light);
      padding: 40px 0 25px;
      color: var(--text-sub);
    }

    .footer-links-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
    }

    .footer-links-wrap a {
      font-size: 0.88rem;
      color: var(--text-sub);
      transition: var(--transition-base);
    }

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

    .footer-bottom {
      text-align: center;
      font-size: 0.82rem;
      color: var(--text-muted);
      border-top: 1px solid #f1f5f9;
      padding-top: 20px;
    }

    /* 浮动客服入口 */
    .floating-kefu {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .btn-float {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--primary-gradient);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 16px rgba(37, 99, 235, 0.4);
      cursor: pointer;
      border: none;
      font-size: 1.1rem;
      transition: var(--transition-base);
    }

    .btn-float:hover {
      transform: scale(1.1);
    }

    /* 响应式媒体查询 */
    @media (max-width: 992px) {
      .hero-h1 {
        font-size: 2.2rem;
      }
      .hero-metrics-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-scenarios {
        grid-template-columns: repeat(2, 1fr);
      }
      .flow-steps {
        grid-template-columns: repeat(2, 1fr);
      }
      .review-grid {
        grid-template-columns: 1fr;
      }
      .media-card-grid {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 768px) {
      .mobile-menu-btn {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 76px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 15px 20px;
        border-bottom: 1px solid var(--border-light);
        box-shadow: var(--shadow-md);
      }
      .nav-links.active {
        display: flex;
      }
      .nav-item a {
        width: 100%;
        display: block;
        padding: 10px 0;
      }
      .hero-h1 {
        font-size: 1.8rem;
      }
      .hero-desc {
        font-size: 0.95rem;
      }
      .grid-scenarios {
        grid-template-columns: 1fr;
      }
      .form-grid {
        grid-template-columns: 1fr;
      }
      .form-group.full, .btn-submit {
        grid-column: span 1;
      }
      .contact-grid {
        grid-template-columns: 1fr;
      }
      .review-score-banner {
        flex-direction: column;
        align-items: flex-start;
      }
    }