/* roulang page: index */
:root {
      --primary: #0F2438;
      --primary-light: #16324F;
      --accent: #00D2FF;
      --accent-warm: #FF9F1C;
      --bg-light: #F4F7F9;
      --bg-white: #FFFFFF;
      --bg-alt: #EBF0F5;
      --bg-dark: #0B131E;
      --text-main: #111827;
      --text-muted: #4B5563;
      --text-light: #9CA3AF;
      --border: #E2E8F0;
      --border-dark: #1E293B;
      --radius-sm: 6px;
      --radius-md: 8px;
      --radius-full: 9999px;
      --shadow-sm: 0 2px 4px rgba(15,36,56,0.04);
      --shadow-md: 0 4px 12px rgba(15,36,56,0.08);
      --shadow-lg: 0 10px 25px rgba(15,36,56,0.12);
      --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }

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

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

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      color: var(--text-main);
      background-color: var(--bg-light);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }

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

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

    button, input, select, textarea {
      font-family: inherit;
    }

    .container {
      width: 100%;
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 2rem;
      padding-right: 2rem;
    }

    .section {
      padding: 5rem 0;
      position: relative;
    }

    .section-header {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 3.5rem auto;
    }

    .section-tag {
      display: inline-block;
      padding: 0.25rem 1rem;
      background: rgba(0, 210, 255, 0.1);
      color: #0284c7;
      font-size: 0.875rem;
      font-weight: 600;
      border-radius: var(--radius-full);
      margin-bottom: 0.75rem;
      border: 1px solid rgba(0, 210, 255, 0.25);
    }

    .section-tag.dark {
      background: rgba(0, 210, 255, 0.15);
      color: var(--accent);
      border-color: rgba(0, 210, 255, 0.3);
    }

    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      line-height: 1.3;
      color: var(--text-main);
      margin-bottom: 1rem;
      letter-spacing: -0.02em;
    }

    .section-title.light {
      color: #FFFFFF;
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
      line-height: 1.7;
    }

    .section-desc.light {
      color: var(--text-light);
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 2rem;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 1.5rem;
    }

    .grid-6 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.5rem;
    }

    .card {
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      padding: 1.75rem;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      position: relative;
      overflow: hidden;
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(0, 210, 255, 0.4);
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.75rem 1.75rem;
      font-size: 1rem;
      font-weight: 600;
      border-radius: var(--radius-sm);
      cursor: pointer;
      transition: var(--transition);
      border: 1px solid transparent;
      line-height: 1.25;
    }

    .btn-primary {
      background: var(--primary);
      color: #FFFFFF;
      border-color: var(--primary);
    }

    .btn-primary:hover {
      background: var(--primary-light);
      border-color: var(--primary-light);
      box-shadow: 0 4px 12px rgba(15, 36, 56, 0.25);
    }

    .btn-accent {
      background: var(--accent);
      color: var(--bg-dark);
      border-color: var(--accent);
    }

    .btn-accent:hover {
      background: #33dcff;
      box-shadow: 0 4px 14px rgba(0, 210, 255, 0.4);
    }

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

    .btn-outline:hover {
      background: rgba(15, 36, 56, 0.05);
    }

    .btn-outline-white {
      background: transparent;
      color: #FFFFFF;
      border-color: rgba(255, 255, 255, 0.4);
    }

    .btn-outline-white:hover {
      border-color: #FFFFFF;
      background: rgba(255, 255, 255, 0.1);
    }

    /* 顶部通栏 */
    .top-bar {
      background: var(--bg-dark);
      color: var(--text-light);
      font-size: 0.8125rem;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
      padding: 0.4rem 0;
    }

    .top-bar-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .top-bar-item {
      display: flex;
      align-items: center;
      gap: 1.25rem;
    }

    .top-bar span {
      display: inline-flex;
      align-items: center;
      gap: 0.35rem;
    }

    /* 主导航 */
    .main-nav {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border);
      box-shadow: 0 2px 8px rgba(0,0,0,0.03);
    }

    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 4.5rem;
    }

    .brand-logo {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      font-size: 1.35rem;
      font-weight: 800;
      color: var(--primary);
      letter-spacing: -0.02em;
    }

    .brand-icon {
      width: 2.25rem;
      height: 2.25rem;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      border-radius: var(--radius-sm);
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-weight: 900;
      font-size: 1rem;
    }

    .nav-menu {
      display: flex;
      align-items: center;
      list-style: none;
      gap: 1.5rem;
    }

    .nav-link {
      font-size: 0.9375rem;
      font-weight: 500;
      color: var(--text-muted);
      padding: 0.5rem 0.25rem;
      position: relative;
    }

    .nav-link:hover, .nav-link.active {
      color: var(--primary);
      font-weight: 600;
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: var(--transition);
    }

    .nav-link:hover::after, .nav-link.active::after {
      width: 100%;
    }

    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      color: var(--primary);
      cursor: pointer;
    }

    /* 首屏帮助搜索与服务大图 Hero */
    .hero-section {
      background: linear-gradient(180deg, #0F2438 0%, #16324F 65%, #F4F7F9 100%);
      padding: 4.5rem 0 5rem 0;
      color: #FFFFFF;
      position: relative;
      overflow: hidden;
    }

    .hero-bg-overlay {
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      opacity: 0.15;
      background-image: url('/assets/images/3064e2592b3bfca8.webp');
      background-size: cover;
      background-position: center;
      mix-blend-mode: overlay;
      pointer-events: none;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 880px;
      margin: 0 auto;
      text-align: center;
    }

    .hero-h1 {
      font-size: 2.75rem;
      font-weight: 800;
      line-height: 1.25;
      margin-bottom: 1.25rem;
      color: #FFFFFF;
    }

    .hero-h1 span {
      background: linear-gradient(90deg, #FFFFFF, var(--accent));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-p {
      font-size: 1.125rem;
      color: #E2E8F0;
      line-height: 1.8;
      margin-bottom: 2rem;
      max-width: 760px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-search-box {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      padding: 0.5rem 0.5rem 0.5rem 1.25rem;
      display: flex;
      align-items: center;
      box-shadow: 0 12px 32px rgba(0,0,0,0.25);
      max-width: 640px;
      margin: 0 auto 1.5rem auto;
    }

    .hero-search-box input {
      flex: 1;
      border: none;
      outline: none;
      font-size: 1rem;
      color: var(--text-main);
    }

    .chips-group {
      display: flex;
      align-items: center;
      justify-content: center;
      flex-wrap: wrap;
      gap: 0.5rem;
      margin-bottom: 2rem;
    }

    .chip-item {
      font-size: 0.8125rem;
      background: rgba(255, 255, 255, 0.12);
      border: 1px solid rgba(255, 255, 255, 0.2);
      color: #F8FAFC;
      padding: 0.3rem 0.85rem;
      border-radius: var(--radius-full);
      backdrop-filter: blur(4px);
    }

    .chip-item:hover {
      background: rgba(0, 210, 255, 0.25);
      border-color: var(--accent);
      color: #FFFFFF;
    }

    /* 1. 核心巡检指标看板 */
    .metric-card {
      background: var(--bg-white);
      border-top: 4px solid var(--accent);
      text-align: center;
      padding: 2.25rem 1.5rem;
    }

    .metric-val {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1;
      margin-bottom: 0.5rem;
      font-variant-numeric: tabular-nums;
    }

    .metric-val span {
      font-size: 1.25rem;
      color: var(--accent-warm);
      font-weight: 600;
    }

    .metric-name {
      font-size: 1.05rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 0.5rem;
    }

    .metric-note {
      font-size: 0.875rem;
      color: var(--text-muted);
    }

    /* 2. 产品与技术矩阵 */
    .product-img-wrap {
      height: 200px;
      overflow: hidden;
      border-radius: var(--radius-sm);
      margin-bottom: 1.25rem;
      position: relative;
    }

    .product-tag {
      position: absolute;
      top: 10px;
      left: 10px;
      background: var(--primary);
      color: #fff;
      font-size: 0.75rem;
      padding: 0.2rem 0.6rem;
      border-radius: 4px;
    }

    .product-specs {
      list-style: none;
      margin: 1rem 0 1.5rem 0;
      font-size: 0.875rem;
      color: var(--text-muted);
      border-top: 1px dashed var(--border);
      border-bottom: 1px dashed var(--border);
      padding: 0.75rem 0;
    }

    .product-specs li {
      display: flex;
      justify-content: space-between;
      margin-bottom: 0.35rem;
    }

    .product-specs li:last-child {
      margin-bottom: 0;
    }

    /* 3. 效能对比表 */
    .compare-container {
      background: var(--bg-white);
      border-radius: var(--radius-md);
      border: 1px solid var(--border);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .compare-row {
      display: grid;
      grid-template-columns: 1.5fr 2fr 2fr;
      padding: 1.25rem 2rem;
      border-bottom: 1px solid var(--border);
      align-items: center;
    }

    .compare-row.header {
      background: var(--bg-alt);
      font-weight: 700;
      color: var(--primary);
    }

    .compare-row:last-child {
      border-bottom: none;
    }

    .compare-cell-old {
      color: #64748B;
      font-size: 0.9375rem;
    }

    .compare-cell-new {
      color: #0F766E;
      font-weight: 600;
      font-size: 0.9375rem;
    }

    /* 4. 多场景服务 */
    .scene-card {
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      padding: 1.5rem;
    }

    .scene-icon-title {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      margin-bottom: 0.75rem;
    }

    .scene-badge {
      width: 2rem;
      height: 2rem;
      background: rgba(0, 210, 255, 0.1);
      border-radius: var(--radius-sm);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-weight: bold;
    }

    /* 5. 深色夜视巡检技术 */
    .dark-tech-section {
      background-color: var(--bg-dark);
      color: #FFFFFF;
      background-image: radial-gradient(circle at 80% 20%, rgba(0, 210, 255, 0.08) 0%, transparent 50%);
    }

    .dark-card {
      background: rgba(255, 255, 255, 0.03);
      border: 1px solid var(--border-dark);
      border-radius: var(--radius-md);
      padding: 1.75rem;
      backdrop-filter: blur(8px);
    }

    .dark-card:hover {
      border-color: var(--accent);
      background: rgba(255, 255, 255, 0.06);
    }

    .dark-card h3 {
      color: #FFFFFF;
      font-size: 1.2rem;
      margin-bottom: 0.75rem;
    }

    .dark-card p {
      color: var(--text-light);
      font-size: 0.9375rem;
    }

    /* 6. 里程碑时间线 */
    .timeline {
      position: relative;
      max-width: 860px;
      margin: 0 auto;
    }

    .timeline::before {
      content: '';
      position: absolute;
      top: 0;
      bottom: 0;
      left: 50%;
      width: 2px;
      background: var(--border);
      transform: translateX(-50%);
    }

    .timeline-item {
      position: relative;
      margin-bottom: 2.5rem;
      width: 50%;
      padding: 0 2rem;
    }

    .timeline-item.left {
      left: 0;
      text-align: right;
    }

    .timeline-item.right {
      left: 50%;
      text-align: left;
    }

    .timeline-dot {
      position: absolute;
      top: 0.5rem;
      width: 14px;
      height: 14px;
      background: var(--accent);
      border: 3px solid #fff;
      border-radius: 50%;
      box-shadow: 0 0 0 2px var(--primary);
    }

    .timeline-item.left .timeline-dot {
      right: -7px;
    }

    .timeline-item.right .timeline-dot {
      left: -7px;
    }

    .timeline-box {
      background: var(--bg-white);
      padding: 1.25rem;
      border-radius: var(--radius-md);
      border: 1px solid var(--border);
    }

    /* 7. 案例故事 */
    .case-card {
      display: flex;
      flex-direction: column;
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      overflow: hidden;
    }

    .case-img-wrap {
      height: 240px;
    }

    .case-content {
      padding: 1.75rem;
      flex: 1;
    }

    .case-stat {
      display: flex;
      gap: 1.5rem;
      margin-top: 1rem;
      padding-top: 1rem;
      border-top: 1px solid var(--border);
    }

    .case-stat-item b {
      font-size: 1.25rem;
      color: var(--primary);
    }

    .case-stat-item span {
      font-size: 0.8125rem;
      color: var(--text-muted);
      display: block;
    }

    /* 8. 评价 */
    .testi-card {
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      padding: 1.75rem;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .testi-quote {
      font-size: 0.9375rem;
      color: var(--text-muted);
      margin-bottom: 1.25rem;
      line-height: 1.7;
    }

    .testi-user {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      border-top: 1px solid var(--border);
      padding-top: 1rem;
    }

    .user-avatar-tag {
      width: 2.5rem;
      height: 2.5rem;
      background: var(--bg-alt);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: bold;
      color: var(--primary);
    }

    /* 9. 行业资讯 */
    .news-card {
      background: var(--bg-white);
      border-radius: var(--radius-md);
      border: 1px solid var(--border);
      overflow: hidden;
      display: flex;
      flex-direction: column;
    }

    .news-body {
      padding: 1.5rem;
      flex: 1;
    }

    .news-date {
      font-size: 0.8125rem;
      color: var(--text-light);
      margin-bottom: 0.5rem;
    }

    .news-title {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 0.5rem;
      line-height: 1.4;
    }

    /* 10. 合规保障 */
    .cert-card {
      text-align: center;
      background: var(--bg-white);
      border: 1px solid var(--border);
      padding: 1.75rem 1rem;
      border-radius: var(--radius-md);
    }

    .cert-icon {
      font-size: 2rem;
      margin-bottom: 0.75rem;
      color: var(--primary);
    }

    /* 11. FAQ 手风琴 */
    .faq-list {
      max-width: 860px;
      margin: 0 auto;
    }

    .faq-item {
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      margin-bottom: 1rem;
      overflow: hidden;
    }

    .faq-question {
      padding: 1.25rem 1.5rem;
      font-weight: 700;
      font-size: 1.05rem;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
    }

    .faq-answer {
      padding: 0 1.5rem 1.25rem 1.5rem;
      color: var(--text-muted);
      font-size: 0.9375rem;
      line-height: 1.7;
    }

    /* 12. 转化表单 */
    .cta-wrapper {
      background: linear-gradient(135deg, var(--primary) 0%, #16324F 100%);
      border-radius: var(--radius-md);
      padding: 3.5rem 3rem;
      color: #FFFFFF;
    }

    .form-group {
      margin-bottom: 1.25rem;
    }

    .form-label {
      display: block;
      font-size: 0.875rem;
      margin-bottom: 0.4rem;
      color: #E2E8F0;
    }

    .form-control {
      width: 100%;
      padding: 0.75rem 1rem;
      border-radius: var(--radius-sm);
      border: 1px solid rgba(255, 255, 255, 0.2);
      background: rgba(255, 255, 255, 0.08);
      color: #FFFFFF;
      font-size: 0.9375rem;
      outline: none;
    }

    .form-control:focus {
      border-color: var(--accent);
      background: rgba(255, 255, 255, 0.15);
    }

    .form-control option {
      background: var(--primary);
      color: #FFFFFF;
    }

    /* 页脚 */
    .footer {
      background: var(--bg-dark);
      color: var(--text-light);
      padding: 4.5rem 0 2rem 0;
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      font-size: 0.9375rem;
    }

    .footer-title {
      color: #FFFFFF;
      font-size: 1.05rem;
      font-weight: 700;
      margin-bottom: 1.25rem;
    }

    .footer-links {
      list-style: none;
    }

    .footer-links li {
      margin-bottom: 0.6rem;
    }

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

    .footer-bottom {
      margin-top: 3.5rem;
      padding-top: 1.5rem;
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      text-align: center;
      font-size: 0.8125rem;
      color: #64748B;
    }

    /* 响应式适配 */
    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .grid-6 { grid-template-columns: repeat(2, 1fr); }
    }

    @media (max-width: 768px) {
      .container { padding-left: 1rem; padding-right: 1rem; }
      .section { padding: 3.5rem 0; }
      .top-bar { display: none; }
      .nav-menu { display: none; }
      .nav-menu.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 4.5rem;
        left: 0;
        right: 0;
        background: #FFFFFF;
        padding: 1.5rem;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow-lg);
      }
      .mobile-toggle { display: block; }
      .grid-2, .grid-3, .grid-4, .grid-6 { grid-template-columns: 1fr; }
      .hero-h1 { font-size: 2rem; }
      .compare-row { grid-template-columns: 1fr; gap: 0.5rem; text-align: left; }
      .timeline::before { left: 1.5rem; }
      .timeline-item { width: 100%; left: 0 !important; text-align: left !important; padding-left: 3.5rem; padding-right: 0; }
      .timeline-item .timeline-dot { left: 1rem !important; }
      .cta-wrapper { padding: 2rem 1.25rem; }
    }