/* roulang page: index */
:root {
      --primary: #0052D9;
      --primary-hover: #003cab;
      --primary-soft: rgba(0, 82, 217, 0.08);
      --accent: #00A870;
      --accent-hover: #00875a;
      --dark: #0A192F;
      --dark-card: #112240;
      --gray-bg: #F5F7FA;
      --text-main: #1D2129;
      --text-muted: #4E5969;
      --text-sub: #86909C;
      --card-border: rgba(229, 230, 235, 0.85);
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
      --shadow-sm: 0 4px 16px rgba(0, 82, 217, 0.05);
      --shadow-md: 0 8px 24px rgba(0, 82, 217, 0.08);
      --shadow-hover: 0 14px 36px rgba(0, 82, 217, 0.12);
      --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      color: var(--text-main);
      background-color: #FFFFFF;
      line-height: 1.65;
      overflow-x: hidden;
    }

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

    /* 顶部辅助行 */
    .top-bar {
      background-color: var(--dark);
      color: #C1C7D0;
      font-size: 0.85rem;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
      padding: 7px 0;
    }

    /* 沉浸式透明玻璃导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 1030;
      background: rgba(255, 255, 255, 0.88);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border-bottom: 1px solid rgba(229, 230, 235, 0.8);
      transition: var(--transition);
    }
    .site-header.scrolled {
      background: #FFFFFF;
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    }
    .navbar-brand {
      font-size: 1.35rem;
      font-weight: 700;
      color: var(--primary) !important;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .nav-link {
      font-weight: 500;
      color: var(--text-muted) !important;
      padding: 0.5rem 1rem !important;
      transition: var(--transition);
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary) !important;
    }

    /* 核心视觉 Hero */
    .hero-section {
      position: relative;
      background: linear-gradient(135deg, rgba(10, 25, 47, 0.88) 0%, rgba(0, 82, 217, 0.82) 100%),
                  url('/assets/images/dcb326551031de86.webp') center/cover no-repeat;
      color: #FFFFFF;
      padding: 110px 0 100px;
    }
    .hero-pill {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 16px;
      background: rgba(255, 255, 255, 0.15);
      border: 1px solid rgba(255, 255, 255, 0.25);
      border-radius: 50px;
      font-size: 0.875rem;
      backdrop-filter: blur(6px);
      margin-bottom: 24px;
    }
    .hero-title {
      font-size: clamp(2.2rem, 4vw, 3.4rem);
      font-weight: 800;
      line-height: 1.25;
      margin-bottom: 24px;
      letter-spacing: -0.5px;
    }
    .hero-desc {
      font-size: 1.125rem;
      color: rgba(255, 255, 255, 0.9);
      max-width: 820px;
      margin-bottom: 38px;
    }

    /* 统一按钮体系 */
    .btn-brand-primary {
      background-color: #FFFFFF;
      color: var(--primary);
      font-weight: 600;
      padding: 12px 28px;
      border-radius: 50px;
      border: 2px solid #FFFFFF;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-brand-primary:hover {
      background-color: var(--primary);
      color: #FFFFFF;
      border-color: #FFFFFF;
    }
    .btn-brand-outline {
      background: rgba(255, 255, 255, 0.1);
      color: #FFFFFF;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: 50px;
      border: 2px solid rgba(255, 255, 255, 0.6);
      backdrop-filter: blur(8px);
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-brand-outline:hover {
      background: #FFFFFF;
      color: var(--dark);
      border-color: #FFFFFF;
    }
    .btn-solid-blue {
      background-color: var(--primary);
      color: #FFFFFF;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: 50px;
      border: none;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-solid-blue:hover {
      background-color: var(--primary-hover);
      color: #FFFFFF;
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(0, 82, 217, 0.25);
    }

    /* 区域统一间距与标题 */
    .sec-py {
      padding: 85px 0;
    }
    .bg-light-gray {
      background-color: var(--gray-bg);
    }
    .bg-dark-section {
      background-color: var(--dark);
      color: #FFFFFF;
    }
    .sec-header {
      margin-bottom: 50px;
    }
    .sec-badge {
      display: inline-block;
      padding: 5px 14px;
      border-radius: 50px;
      background: var(--primary-soft);
      color: var(--primary);
      font-size: 0.85rem;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .sec-badge-dark {
      background: rgba(255, 255, 255, 0.12);
      color: #4ade80;
    }
    .sec-title {
      font-size: 2.15rem;
      font-weight: 700;
      margin-bottom: 16px;
      letter-spacing: -0.3px;
    }
    .sec-desc {
      color: var(--text-muted);
      font-size: 1.05rem;
      max-width: 760px;
      margin-left: auto;
      margin-right: auto;
    }

    /* 卡片系统 */
    .ui-card {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      border: 1px solid var(--card-border);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      height: 100%;
    }
    .ui-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
      border-color: rgba(0, 82, 217, 0.2);
    }
    .card-icon-box {
      width: 56px;
      height: 56px;
      border-radius: 12px;
      background: var(--primary-soft);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.65rem;
      margin-bottom: 20px;
    }

    /* 指标看板 */
    .metric-card {
      background: #FFFFFF;
      padding: 32px 24px;
      border-radius: var(--radius-md);
      border: 1px solid var(--card-border);
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: var(--transition);
    }
    .metric-card:hover {
      border-color: var(--primary);
      box-shadow: var(--shadow-md);
    }
    .metric-num {
      font-size: 2.75rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.1;
      margin-bottom: 8px;
    }
    .metric-label {
      font-weight: 600;
      font-size: 1.05rem;
      margin-bottom: 6px;
    }

    /* 对比表格面板 */
    .comp-col-bad {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      border: 1px solid #E2E8F0;
      padding: 35px 28px;
    }
    .comp-col-good {
      background: linear-gradient(180deg, #F0F7FF 0%, #FFFFFF 100%);
      border-radius: var(--radius-md);
      border: 2px solid var(--primary);
      padding: 35px 28px;
      position: relative;
    }
    .comp-badge {
      position: absolute;
      top: -14px;
      right: 28px;
      background: var(--primary);
      color: #FFF;
      font-size: 0.8rem;
      padding: 4px 12px;
      border-radius: 50px;
      font-weight: 600;
    }

    /* 时间轴里程碑 */
    .timeline-step {
      position: relative;
      padding-left: 36px;
      border-left: 2px dashed rgba(0, 82, 217, 0.35);
      margin-bottom: 35px;
    }
    .timeline-step::before {
      content: "";
      position: absolute;
      left: -9px;
      top: 0;
      width: 16px;
      height: 16px;
      border-radius: 50%;
      background: #FFFFFF;
      border: 3px solid var(--primary);
    }

    /* 手风琴改造 */
    .custom-accordion .accordion-item {
      border: 1px solid var(--card-border);
      border-radius: var(--radius-sm) !important;
      margin-bottom: 14px;
      overflow: hidden;
    }
    .custom-accordion .accordion-button {
      font-weight: 600;
      color: var(--text-main);
      padding: 18px 22px;
      background: #FFFFFF;
    }
    .custom-accordion .accordion-button:not(.collapsed) {
      background: var(--primary-soft);
      color: var(--primary);
      box-shadow: none;
    }
    .custom-accordion .accordion-body {
      padding: 18px 22px;
      color: var(--text-muted);
      line-height: 1.7;
    }

    /* 页脚 */
    .site-footer {
      background-color: #0c1322;
      color: #94A3B8;
      padding: 70px 0 25px;
      font-size: 0.95rem;
      border-top: 1px solid rgba(255, 255, 255, 0.08);
    }
    .site-footer a {
      color: #CBD5E1;
    }
    .site-footer a:hover {
      color: #FFFFFF;
    }
    .footer-title {
      color: #FFFFFF;
      font-weight: 700;
      font-size: 1.15rem;
      margin-bottom: 22px;
    }