:root {
      --bg-main: #f8fafc;
      --bg-card: #ffffff;
      --bg-card-alt: #f1f5f9;
      --text-main: #0f172a;
      --text-muted: #475569;
      --neon-cyan: #00e5ff;
      --neon-magenta: #ff007f;
      --neon-purple: #7928ca;
      --neon-blue: #0066ff;
      --border-light: rgba(121, 40, 202, 0.15);
      --neon-glow: 0 0 15px rgba(0, 229, 255, 0.35), 0 0 30px rgba(255, 0, 127, 0.2);
      --container-width: 1200px;
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      -webkit-tap-highlight-color: transparent;
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-main);
      background-image: 
        radial-gradient(circle at 10% 20%, rgba(0, 229, 255, 0.07) 0%, transparent 40%),
        radial-gradient(circle at 90% 40%, rgba(255, 0, 127, 0.06) 0%, transparent 45%),
        radial-gradient(circle at 50% 80%, rgba(121, 40, 202, 0.05) 0%, transparent 50%);
      background-attachment: fixed;
      color: var(--text-main);
      line-height: 1.65;
      overflow-x: hidden;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: all 0.25s ease;
    }

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

    /* 顶部导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 999;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.2);
      box-shadow: 0 4px 20px rgba(15, 23, 42, 0.04);
    }

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

    .brand-box {
      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;
    }

    .brand-title span {
      background: linear-gradient(90deg, var(--neon-blue), var(--neon-magenta));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

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

    .nav-links li a {
      display: inline-block;
      padding: 10px 14px;
      font-size: 0.95rem;
      font-weight: 600;
      color: var(--text-main);
      position: relative;
    }

    .nav-links li a:hover {
      color: var(--neon-magenta);
    }

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

    .btn-neon {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 22px;
      font-size: 0.95rem;
      font-weight: 700;
      color: #ffffff;
      background: linear-gradient(135deg, var(--neon-blue) 0%, var(--neon-purple) 50%, var(--neon-magenta) 100%);
      border-radius: var(--radius-sm);
      border: 1px solid rgba(255, 255, 255, 0.4);
      box-shadow: 0 4px 15px rgba(121, 40, 202, 0.35);
      cursor: pointer;
      transition: all 0.3s ease;
    }

    .btn-neon:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 22px rgba(255, 0, 127, 0.45);
      color: #ffffff;
    }

    .btn-outline {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 9px 20px;
      font-size: 0.95rem;
      font-weight: 600;
      color: var(--text-main);
      background: #ffffff;
      border: 1px solid rgba(0, 229, 255, 0.6);
      border-radius: var(--radius-sm);
      transition: all 0.25s ease;
    }

    .btn-outline:hover {
      border-color: var(--neon-magenta);
      background: rgba(0, 229, 255, 0.08);
      color: var(--neon-magenta);
    }

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

    /* 首屏 Hero (严格不含图片) */
    .hero-section {
      padding: 85px 0 70px;
      text-align: center;
      position: relative;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 16px;
      background: #ffffff;
      border: 1px solid rgba(0, 229, 255, 0.5);
      border-radius: 30px;
      box-shadow: 0 2px 12px rgba(0, 229, 255, 0.2);
      font-size: 0.88rem;
      font-weight: 700;
      color: var(--neon-purple);
      margin-bottom: 24px;
    }

    .hero-title {
      font-size: 2.75rem;
      font-weight: 900;
      line-height: 1.25;
      letter-spacing: -0.5px;
      color: var(--text-main);
      max-width: 900px;
      margin: 0 auto 20px;
    }

    .hero-subtitle {
      font-size: 1.15rem;
      color: var(--text-muted);
      max-width: 780px;
      margin: 0 auto 36px;
    }

    .hero-cta-group {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 18px;
      margin-bottom: 45px;
    }

    .btn-large {
      padding: 14px 34px;
      font-size: 1.05rem;
    }

    .hero-metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      margin-top: 20px;
    }

    .metric-card {
      background: #ffffff;
      border: 1px solid rgba(121, 40, 202, 0.12);
      border-top: 3px solid var(--neon-cyan);
      border-radius: var(--radius-md);
      padding: 24px 18px;
      box-shadow: 0 4px 20px rgba(15, 23, 42, 0.04);
      transition: all 0.3s ease;
    }

    .metric-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 10px 25px rgba(0, 229, 255, 0.18);
      border-top-color: var(--neon-magenta);
    }

    .metric-val {
      font-size: 1.85rem;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 6px;
    }

    .metric-desc {
      font-size: 0.9rem;
      color: var(--text-muted);
    }

    /* 通用章节规范 */
    .section-wrap {
      padding: 65px 0;
      position: relative;
    }

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

    .section-tag {
      display: inline-block;
      padding: 4px 14px;
      background: rgba(0, 229, 255, 0.1);
      border: 1px solid rgba(0, 229, 255, 0.4);
      border-radius: 20px;
      font-size: 0.85rem;
      font-weight: 700;
      color: var(--neon-blue);
      text-transform: uppercase;
      margin-bottom: 10px;
    }

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

    .section-sub {
      font-size: 1rem;
      color: var(--text-muted);
      max-width: 680px;
      margin: 0 auto;
    }

    /* 卡片网格系统 */
    .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;
    }

    .neon-card {
      background: var(--bg-card);
      border: 1px solid rgba(121, 40, 202, 0.12);
      border-radius: var(--radius-md);
      padding: 28px 24px;
      box-shadow: 0 4px 20px rgba(15, 23, 42, 0.03);
      position: relative;
      transition: all 0.3s ease;
    }

    .neon-card:hover {
      transform: translateY(-5px);
      border-color: var(--neon-magenta);
      box-shadow: 0 12px 30px rgba(255, 0, 127, 0.12);
    }

    .neon-card h3 {
      font-size: 1.22rem;
      font-weight: 700;
      margin-bottom: 12px;
      color: var(--text-main);
    }

    .neon-card p {
      font-size: 0.94rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* 模型矩阵徽章池 */
    .models-pool {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 30px;
    }

    .model-chip {
      padding: 8px 16px;
      background: #ffffff;
      border: 1px solid rgba(0, 102, 255, 0.2);
      border-radius: 20px;
      font-size: 0.88rem;
      font-weight: 600;
      color: var(--text-main);
      box-shadow: 0 2px 8px rgba(15, 23, 42, 0.04);
      transition: all 0.2s ease;
    }

    .model-chip:hover {
      background: linear-gradient(135deg, rgba(0, 229, 255, 0.1), rgba(255, 0, 127, 0.1));
      border-color: var(--neon-magenta);
      transform: scale(1.05);
      color: var(--neon-purple);
    }

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

    .step-card {
      background: #ffffff;
      border: 1px solid rgba(0, 229, 255, 0.3);
      border-radius: var(--radius-md);
      padding: 26px 20px;
      position: relative;
    }

    .step-number {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 38px;
      height: 38px;
      background: linear-gradient(135deg, var(--neon-cyan), var(--neon-blue));
      color: #ffffff;
      font-weight: 800;
      border-radius: 50%;
      margin-bottom: 14px;
      box-shadow: 0 4px 10px rgba(0, 102, 255, 0.3);
    }

    .step-card h4 {
      font-size: 1.1rem;
      margin-bottom: 8px;
      color: var(--text-main);
    }

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

    /* 案例展示区（含图片） */
    .case-gallery {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .case-item {
      background: #ffffff;
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid rgba(121, 40, 202, 0.15);
      box-shadow: 0 6px 24px rgba(15, 23, 42, 0.05);
    }

    .case-img-box {
      width: 100%;
      overflow: hidden;
      background: #e2e8f0;
      aspect-ratio: 16 / 9;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .case-img-box img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s ease;
    }

    .case-item:hover .case-img-box img {
      transform: scale(1.03);
    }

    .case-info {
      padding: 22px;
    }

    .case-info h4 {
      font-size: 1.15rem;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .case-info p {
      font-size: 0.92rem;
      color: var(--text-muted);
    }

    /* 对比评测表格与评级卡 */
    .eval-score-box {
      background: #ffffff;
      border: 2px solid var(--neon-magenta);
      border-radius: var(--radius-md);
      padding: 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 30px;
      box-shadow: 0 6px 25px rgba(255, 0, 127, 0.15);
    }

    .eval-left {
      display: flex;
      align-items: center;
      gap: 20px;
    }

    .score-badge {
      font-size: 2.6rem;
      font-weight: 900;
      color: var(--neon-magenta);
      line-height: 1;
    }

    .score-detail h4 {
      font-size: 1.25rem;
      color: var(--text-main);
      margin-bottom: 4px;
    }

    .score-stars {
      color: #ffb800;
      font-size: 1.2rem;
      letter-spacing: 2px;
    }

    .table-container {
      width: 100%;
      overflow-x: auto;
      background: #ffffff;
      border-radius: var(--radius-md);
      border: 1px solid rgba(121, 40, 202, 0.15);
      box-shadow: 0 4px 20px rgba(15, 23, 42, 0.04);
    }

    .eval-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 640px;
    }

    .eval-table th, .eval-table td {
      padding: 16px 20px;
      border-bottom: 1px solid #edf2f7;
      font-size: 0.95rem;
    }

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

    .eval-table tr:hover {
      background: rgba(0, 229, 255, 0.03);
    }

    .eval-highlight {
      font-weight: 700;
      color: var(--neon-blue);
    }

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

    .review-card {
      background: #ffffff;
      border: 1px solid rgba(0, 229, 255, 0.3);
      border-radius: var(--radius-md);
      padding: 24px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      box-shadow: 0 4px 15px rgba(15, 23, 42, 0.04);
    }

    .review-body {
      font-size: 0.94rem;
      color: var(--text-main);
      margin-bottom: 18px;
      font-style: italic;
    }

    .reviewer-meta {
      display: flex;
      align-items: center;
      justify-content: space-between;
      border-top: 1px solid #f1f5f9;
      padding-top: 12px;
    }

    .reviewer-title {
      font-weight: 700;
      font-size: 0.92rem;
      color: var(--neon-purple);
    }

    .reviewer-tag {
      font-size: 0.82rem;
      color: var(--text-muted);
    }

    /* 需求匹配与表单 */
    .form-wrap {
      background: #ffffff;
      border: 1px solid rgba(121, 40, 202, 0.2);
      border-top: 4px solid var(--neon-magenta);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: 0 10px 35px rgba(15, 23, 42, 0.06);
    }

    .form-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 18px;
      margin-bottom: 18px;
    }

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

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

    .form-group label {
      font-size: 0.9rem;
      font-weight: 700;
      color: var(--text-main);
    }

    .form-control {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid #cbd5e1;
      border-radius: var(--radius-sm);
      font-size: 0.95rem;
      color: var(--text-main);
      background: #f8fafc;
      outline: none;
      transition: border-color 0.2s ease;
    }

    .form-control:focus {
      border-color: var(--neon-blue);
      background: #ffffff;
      box-shadow: 0 0 0 3px rgba(0, 102, 255, 0.15);
    }

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

    .faq-item {
      background: #ffffff;
      border: 1px solid rgba(121, 40, 202, 0.15);
      border-radius: var(--radius-sm);
      overflow: hidden;
      transition: all 0.25s ease;
    }

    .faq-header {
      padding: 18px 22px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      cursor: pointer;
      font-weight: 700;
      font-size: 1rem;
      color: var(--text-main);
    }

    .faq-header:hover {
      color: var(--neon-blue);
    }

    .faq-icon {
      font-size: 1.2rem;
      font-weight: 400;
      transition: transform 0.25s ease;
    }

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

    .faq-body {
      display: none;
      padding: 0 22px 18px;
      font-size: 0.94rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

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

    /* 资讯与友情链接 */
    .news-section-box {
      background: #ffffff;
      border-radius: var(--radius-md);
      padding: 28px;
      border: 1px solid rgba(0, 229, 255, 0.2);
    }

    .news-links-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 14px;
      margin-top: 16px;
    }

    .news-link-item {
      display: block;
      padding: 12px 16px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: var(--radius-sm);
      font-size: 0.92rem;
      font-weight: 600;
      color: var(--text-main);
    }

    .news-link-item:hover {
      border-color: var(--neon-magenta);
      color: var(--neon-magenta);
      background: #ffffff;
    }

    /* 底部专属区 */
    .site-footer {
      background: #0b1120;
      color: #94a3b8;
      padding: 60px 0 30px;
      border-top: 2px solid var(--neon-purple);
    }

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

    .footer-col h4 {
      color: #ffffff;
      font-size: 1.1rem;
      margin-bottom: 18px;
      font-weight: 700;
    }

    .footer-col p {
      font-size: 0.9rem;
      line-height: 1.65;
      margin-bottom: 10px;
    }

    .footer-col ul {
      list-style: none;
    }

    .footer-col ul li {
      margin-bottom: 10px;
      font-size: 0.9rem;
    }

    .footer-col ul li a {
      color: #94a3b8;
    }

    .footer-col ul li a:hover {
      color: var(--neon-cyan);
    }

    .qr-card {
      background: #ffffff;
      padding: 10px;
      border-radius: var(--radius-sm);
      display: inline-block;
      max-width: 130px;
    }

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

    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.1);
      padding-top: 24px;
      text-align: center;
      font-size: 0.88rem;
    }

    .friend-links-box {
      margin-bottom: 16px;
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 14px;
    }

    .friend-links-box a {
      color: #cbd5e1;
      font-size: 0.88rem;
    }

    .friend-links-box a:hover {
      color: var(--neon-cyan);
    }

    /* 浮动客服入口 */
    .float-service-bar {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 990;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      background: #ffffff;
      border: 1px solid rgba(0, 229, 255, 0.5);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.25rem;
      color: var(--neon-purple);
      box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
      cursor: pointer;
      transition: all 0.25s ease;
    }

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

    /* 响应式断点 */
    @media (max-width: 992px) {
      .hero-title {
        font-size: 2.1rem;
      }
      .grid-4, .steps-container {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3, .reviews-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .hero-metrics-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .nav-links.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        border-bottom: 1px solid #e2e8f0;
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
        padding: 12px 0;
      }
      .mobile-menu-btn {
        display: block;
      }
      .hero-title {
        font-size: 1.75rem;
      }
      .hero-subtitle {
        font-size: 1rem;
      }
      .grid-3, .grid-4, .steps-container, .case-gallery, .reviews-grid, .form-grid, .footer-grid, .news-links-grid {
        grid-template-columns: 1fr;
      }
      .form-group.full {
        grid-column: span 1;
      }
      .eval-score-box {
        flex-direction: column;
        text-align: center;
        gap: 16px;
      }
      .eval-left {
        flex-direction: column;
      }
      .hero-cta-group {
        flex-direction: column;
        gap: 12px;
      }
    }