/* roulang page: index */
:root {
      --primary: #1E40AF;
      --primary-hover: #1E3A8A;
      --primary-light: #EFF6FF;
      --primary-soft: #F0F6FF;
      --accent: #F59E0B;
      --accent-light: #FFFBEB;
      --gray-50: #F8FAFC;
      --gray-100: #F1F5F9;
      --gray-200: #E2E8F0;
      --gray-300: #CBD5E1;
      --gray-400: #94A3B8;
      --gray-500: #64748B;
      --gray-600: #475569;
      --gray-700: #334155;
      --gray-800: #1E293B;
      --gray-900: #0F172A;
      --white: #FFFFFF;
      --border-light: #E2E8F0;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 10px 25px -5px rgba(0,0,0,0.08), 0 4px 10px -6px rgba(0,0,0,0.05);
      --shadow-nav: 0 0 20px rgba(0,0,0,0.03);
      --radius-card: 16px;
      --radius-btn: 10px;
      --radius-lg: 20px;
      --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--white);
      color: var(--gray-600);
      margin: 0;
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4, .h1, .h2, .h3 {
      font-weight: 600;
      color: var(--gray-800);
      letter-spacing: -0.02em;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container-custom {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    /* 左侧导航栏桌面端 */
    .app-sidebar {
      position: fixed;
      left: 0;
      top: 0;
      width: 240px;
      height: 100vh;
      background: var(--white);
      border-right: 1px solid var(--border-light);
      display: flex;
      flex-direction: column;
      padding: 24px 16px;
      z-index: 1030;
      box-shadow: var(--shadow-nav);
      transition: transform 0.3s ease;
    }
    .sidebar-logo {
      display: flex;
      align-items: center;
      gap: 10px;
      height: 60px;
      margin-bottom: 32px;
      font-weight: 700;
      font-size: 20px;
      color: var(--gray-900);
    }
    .logo-icon {
      width: 36px;
      height: 36px;
      background: linear-gradient(135deg, #1E40AF 0%, #1E3A8A 100%);
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 20px;
    }
    .nav-menu {
      display: flex;
      flex-direction: column;
      gap: 6px;
      flex: 1;
    }
    .nav-link-item {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 0 16px;
      height: 48px;
      border-radius: 10px;
      color: var(--gray-500);
      font-weight: 500;
      border-left: 4px solid transparent;
      transition: all 0.2s;
      background: transparent;
    }
    .nav-link-item i {
      width: 20px;
      font-size: 1.1rem;
      text-align: center;
    }
    .nav-link-item:hover, .nav-link-item.active {
      background: var(--gray-100);
      color: var(--primary);
      border-left-color: var(--primary);
    }
    .main-content {
      margin-left: 240px;
      width: calc(100% - 240px);
    }
    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: white;
      border-bottom: 1px solid var(--border-light);
      align-items: center;
      justify-content: space-between;
      padding: 0 20px;
      z-index: 1025;
    }
    .offcanvas {
      width: 260px !important;
    }
    .offcanvas-body {
      padding: 24px 16px;
    }
    .offcanvas .nav-link-item {
      margin-bottom: 4px;
    }
    /* 区块间距 */
    section {
      padding: 80px 0;
    }
    @media (max-width: 991px) {
      .app-sidebar {
        display: none;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
      }
      .mobile-header {
        display: flex;
      }
      section {
        padding: 60px 0;
      }
    }
    /* 按钮 */
    .btn-primary-custom {
      background: var(--primary);
      border: none;
      color: white;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      transition: background 0.2s;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }
    .btn-primary-custom:hover {
      background: var(--primary-hover);
      color: white;
    }
    .btn-outline-custom {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      transition: all 0.2s;
    }
    .btn-outline-custom:hover {
      background: var(--primary-light);
      color: var(--primary);
    }
    /* 标题下装饰线 */
    .section-title {
      font-size: 28px;
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--gray-800);
      text-align: center;
    }
    .title-underline {
      width: 40px;
      height: 4px;
      background: var(--primary);
      margin: 0 auto 40px;
      border-radius: 2px;
    }
    /* 卡片通用 */
    .card-custom {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      box-shadow: var(--shadow-card);
      transition: box-shadow 0.25s ease, transform 0.2s;
      border: none;
      height: 100%;
    }
    .card-custom:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-2px);
    }
    /* Hero */
    .hero-section {
      background: linear-gradient(135deg, #f0f4ff 0%, #ffffff 100%);
      position: relative;
      overflow: hidden;
      min-height: 90vh;
      display: flex;
      align-items: center;
    }
    .hero-bg-texture {
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      opacity: 0.05;
      pointer-events: none;
    }
    .data-float-card {
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      border-radius: 20px;
      padding: 24px;
      box-shadow: 0 20px 35px -8px rgba(0,0,0,0.08);
      border: 1px solid rgba(255,255,255,0.7);
    }
    /* 指标卡片色条 */
    .metric-accent-blue { border-top: 4px solid var(--primary); }
    .metric-accent-amber { border-top: 4px solid var(--accent); }
    .metric-accent-green { border-top: 4px solid #10B981; }
    .metric-accent-purple { border-top: 4px solid #8B5CF6; }
    .trend-up { color: #10B981; }
    .trend-down { color: #EF4444; }
    /* 服务卡片图片 */
    .service-img-top {
      height: 120px;
      object-fit: cover;
      border-radius: 16px 16px 0 0;
      width: 100%;
      position: relative;
    }
    .service-img-overlay {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 120px;
      background: linear-gradient(180deg, rgba(30,64,175,0.15) 0%, transparent 100%);
      border-radius: 16px 16px 0 0;
    }
    .icon-service {
      font-size: 32px;
      color: var(--gray-500);
      transition: color 0.2s;
    }
    .card-custom:hover .icon-service {
      color: var(--primary);
    }
    /* 对比卡片 */
    .compare-traditional {
      background: #F1F5F9;
      border-radius: 20px;
      padding: 32px;
    }
    .compare-niu {
      background: #FFFFFF;
      border-radius: 20px;
      padding: 32px;
      border-left: 5px solid var(--primary);
      box-shadow: 0 8px 20px rgba(0,0,0,0.02);
    }
    /* FAQ */
    .accordion-button {
      font-weight: 600;
      font-size: 18px;
      background: white;
      border: 1px solid var(--border-light);
      border-radius: 12px !important;
      margin-bottom: 12px;
      box-shadow: none;
      color: var(--gray-800);
    }
    .accordion-button:not(.collapsed) {
      background: #F0F6FF;
      border-color: #BFDBFE;
      color: var(--primary);
      box-shadow: none;
    }
    .accordion-body {
      font-size: 16px;
      line-height: 1.8;
      color: var(--gray-700);
    }
    /* CTA */
    .cta-section {
      background: #F1F5F9;
      border-radius: 32px;
      margin: 40px 20px;
    }
    .input-cta {
      height: 52px;
      border-radius: 10px;
      border: 1.5px solid #CBD5E1;
      padding: 0 20px;
      font-size: 16px;
      outline: none;
    }
    .input-cta:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(30,64,175,0.15);
    }
    /* 页脚 */
    .footer-link {
      color: var(--gray-500);
      margin-bottom: 8px;
    }
    .footer-link:hover {
      color: var(--primary);
    }
    .social-circle {
      width: 36px;
      height: 36px;
      background: #E2E8F0;
      border-radius: 50%;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: #64748B;
      transition: all 0.2s;
    }
    .social-circle:hover {
      background: var(--primary);
      color: white;
    }
    @media (max-width: 768px) {
      .hero-section {
        min-height: auto;
        padding-top: 100px;
      }
      .btn-primary-custom, .btn-outline-custom {
        width: 100%;
        margin-bottom: 12px;
      }
      .data-float-card {
        display: none;
      }
      .section-title {
        font-size: 24px;
      }
    }