/* roulang page: index */
:root {
      --primary: #E8452D;
      --primary-hover: #C0392B;
      --secondary: #0F1A2E;
      --secondary-light: #1B2D4A;
      --bg-light: #F7F8FA;
      --bg-white: #FFFFFF;
      --text-dark: #1E293B;
      --text-muted: #64748B;
      --text-light: #F1F5F9;
      --border-light: rgba(255,255,255,0.1);
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.12);
      --radius-card: 16px;
      --radius-btn: 8px;
      --radius-badge: 20px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --transition: 0.2s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-white);
      color: var(--text-dark);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
      display: flex;
      flex-direction: column;
    }
    h1, h2, h3 {
      font-weight: 700;
    }
    h1 {
      font-size: 3.2rem;
      font-weight: 700;
    }
    h2 {
      font-size: 2rem;
      font-weight: 600;
    }
    h3 {
      font-size: 1.5rem;
    }
    a {
      color: var(--primary);
      text-decoration: none;
      transition: var(--transition);
    }
    a:hover {
      color: var(--primary-hover);
    }
    .btn-primary-custom {
      background-color: var(--primary);
      border: 2px solid var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 0.75rem 2rem;
      font-weight: 600;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }
    .btn-primary-custom:hover {
      background-color: var(--primary-hover);
      border-color: var(--primary-hover);
      color: white;
    }
    .btn-outline-custom {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-btn);
      padding: 0.6rem 1.8rem;
      font-weight: 600;
      transition: var(--transition);
    }
    .btn-outline-custom:hover {
      background-color: rgba(232,69,45,0.05);
      border-color: var(--primary);
      color: var(--primary);
    }
    .badge-custom {
      background: rgba(232,69,45,0.1);
      color: var(--primary);
      font-size: 0.8rem;
      font-weight: 600;
      padding: 4px 12px;
      border-radius: var(--radius-badge);
      white-space: nowrap;
    }
    .text-muted-custom {
      color: var(--text-muted);
    }

    /* 左侧固定导航 App Shell */
    .app-sidebar {
      position: fixed;
      top: 0;
      left: 0;
      width: 240px;
      height: 100vh;
      background: var(--secondary);
      color: white;
      display: flex;
      flex-direction: column;
      z-index: 1030;
      box-shadow: 2px 0 10px rgba(0,0,0,0.15);
    }
    .sidebar-brand {
      padding: 1.5rem 1.5rem;
      font-size: 1.8rem;
      font-weight: 700;
      color: white;
      border-bottom: 1px solid var(--border-light);
    }
    .sidebar-brand span {
      color: var(--primary);
    }
    .sidebar-nav {
      flex: 1;
      padding: 1.5rem 0;
      display: flex;
      flex-direction: column;
    }
    .sidebar-nav a {
      color: rgba(255,255,255,0.75);
      padding: 0.9rem 1.8rem;
      font-weight: 500;
      transition: var(--transition);
      border-left: 3px solid transparent;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .sidebar-nav a:hover,
    .sidebar-nav a.active {
      color: white;
      background: rgba(232,69,45,0.15);
      border-left-color: var(--primary);
      text-decoration: none;
    }
    .sidebar-nav a i {
      width: 20px;
      text-align: center;
    }
    .main-content {
      margin-left: 240px;
      width: calc(100% - 240px);
      background: var(--bg-white);
    }
    /* 移动端汉堡菜单 */
    .navbar-mobile {
      display: none;
      background: var(--secondary);
      padding: 0.8rem 1rem;
    }
    .offcanvas {
      background: var(--secondary);
      color: white;
    }
    .offcanvas .nav-link {
      color: rgba(255,255,255,0.8);
      padding: 1rem 1.5rem;
      border-left: 3px solid transparent;
    }
    .offcanvas .nav-link.active {
      color: white;
      border-left-color: var(--primary);
    }

    /* Hero数据看板 */
    .hero-section {
      background: linear-gradient(135deg, #0F1A2E 0%, #1B2D4A 100%);
      color: white;
      padding: 6rem 3rem 5rem;
      position: relative;
      overflow: hidden;
    }
    .hero-glow {
      position: absolute;
      top: -20%;
      right: -10%;
      width: 60%;
      height: 140%;
      background: radial-gradient(circle, rgba(232,69,45,0.15) 0%, transparent 70%);
      z-index: 0;
    }
    .hero-content {
      position: relative;
      z-index: 1;
    }
    .metric-card {
      background: rgba(255,255,255,0.05);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      padding: 1.5rem;
      backdrop-filter: blur(4px);
    }
    .metric-value {
      font-size: 2rem;
      font-weight: 700;
      color: var(--primary);
      font-variant-numeric: tabular-nums;
    }

    /* 服务矩阵卡片 */
    .service-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      height: 100%;
      border: 1px solid rgba(0,0,0,0.04);
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 56px;
      height: 56px;
      background: rgba(232,69,45,0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1.5rem;
      color: var(--primary);
      font-size: 1.5rem;
    }

    /* 对比模块 */
    .compare-bg {
      background: var(--bg-light);
    }
    .compare-highlight {
      color: var(--primary);
      font-weight: 700;
    }

    /* FAQ */
    .accordion-button:not(.collapsed) {
      background-color: rgba(232,69,45,0.04);
      color: var(--text-dark);
      box-shadow: none;
    }
    .accordion-button:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 0.15rem rgba(232,69,45,0.2);
    }
    .accordion-item {
      border: none;
      border-bottom: 1px solid rgba(0,0,0,0.06);
    }

    /* CTA 表单区 */
    .cta-section {
      background: var(--secondary);
    }
    .input-custom {
      border-radius: var(--radius-btn);
      padding: 0.9rem 1.2rem;
      border: 1px solid rgba(255,255,255,0.2);
      background: rgba(255,255,255,0.08);
      color: white;
      width: 100%;
    }
    .input-custom:focus {
      border-color: var(--primary);
      background: rgba(255,255,255,0.15);
      box-shadow: none;
      outline: 0;
    }

    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: rgba(255,255,255,0.7);
    }
    .footer a {
      color: rgba(255,255,255,0.7);
    }
    .footer a:hover {
      color: var(--primary);
    }

    /* 响应式 */
    @media (max-width: 992px) {
      .app-sidebar {
        display: none;
      }
      .navbar-mobile {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
      }
      h1 {
        font-size: 2.5rem;
      }
    }
    @media (max-width: 768px) {
      .hero-section {
        padding: 4rem 1.5rem 3rem;
      }
      h1 {
        font-size: 2rem;
      }
      .service-card {
        margin-bottom: 1rem;
      }
    }
    @media (max-width: 576px) {
      h1 {
        font-size: 1.8rem;
      }
      .metric-value {
        font-size: 1.5rem;
      }
    }