/* roulang page: index */
:root {
      --primary: #0F172A;
      --accent: #10B981;
      --accent-hover: #059669;
      --neutral-dark: #1E293B;
      --neutral-slate: #334155;
      --text-muted: #64748B;
      --bg-light: #F8FAFC;
      --card-white: #FFFFFF;
      --border-subtle: #E2E8F0;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-subtle: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
      --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    }

    /* Reset & Base */
    *, *::before, *::after { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
      color: var(--neutral-slate);
      background-color: var(--bg-light);
      line-height: 1.6;
      margin: 0;
      padding: 0;
    }
    h1, h2, h3, h4, h5, h6 {
      color: var(--primary);
      font-weight: 700;
      letter-spacing: -0.01em;
    }
    a { text-decoration: none; color: inherit; }
    img { max-width: 100%; height: auto; display: block; }

    /* Top Strip */
    .top-strip {
      background-color: #070B12;
      color: var(--text-muted);
      font-size: 0.8125rem;
      padding: 0.4rem 0;
      border-bottom: 1px solid rgba(255,255,255,0.06);
    }
    .top-strip .status-dot {
      display: inline-block;
      width: 7px;
      height: 7px;
      background-color: var(--accent);
      border-radius: 50%;
      margin-right: 6px;
      box-shadow: 0 0 6px var(--accent);
    }

    /* Header & Navigation (Creator Platform Style) */
    .site-header {
      background: rgba(15, 23, 42, 0.94);
      backdrop-filter: blur(12px);
      position: sticky;
      top: 0;
      z-index: 1030;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
      transition: all 0.25s ease;
    }
    .brand-logo {
      display: inline-flex;
      align-items: center;
      gap: 0.65rem;
      font-size: 1.25rem;
      font-weight: 800;
      color: #FFFFFF;
      letter-spacing: -0.02em;
    }
    .brand-logo .brand-icon {
      width: 32px;
      height: 32px;
      background: linear-gradient(135deg, var(--accent) 0%, #047857 100%);
      border-radius: 6px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #FFFFFF;
      font-size: 0.9rem;
    }
    .nav-link-custom {
      color: #94A3B8;
      font-size: 0.9375rem;
      font-weight: 500;
      padding: 0.5rem 0.85rem;
      transition: color 0.2s ease;
    }
    .nav-link-custom:hover {
      color: #FFFFFF;
    }
    .nav-search-box {
      position: relative;
      display: inline-flex;
      align-items: center;
    }
    .nav-search-input {
      background: rgba(255, 255, 255, 0.07);
      border: 1px solid rgba(255, 255, 255, 0.12);
      border-radius: 6px;
      color: #F8FAFC;
      font-size: 0.825rem;
      padding: 0.35rem 2rem 0.35rem 0.85rem;
      outline: none;
      width: 170px;
      transition: width 0.25s ease, border-color 0.25s ease;
    }
    .nav-search-input:focus {
      width: 210px;
      border-color: var(--accent);
      background: rgba(255, 255, 255, 0.12);
    }
    .nav-search-input::placeholder { color: #64748B; }
    .nav-search-box i {
      position: absolute;
      right: 0.75rem;
      color: #64748B;
      font-size: 0.8rem;
    }
    .btn-emerald {
      background-color: var(--accent);
      color: #064E3B;
      font-weight: 700;
      font-size: 0.875rem;
      border-radius: var(--radius-btn);
      padding: 0.45rem 1.15rem;
      border: none;
      transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
    }
    .btn-emerald:hover {
      background-color: #34D399;
      color: #022C22;
      transform: translateY(-2px);
      box-shadow: 0 4px 14px rgba(16, 185, 129, 0.35);
    }

    /* Section Global System */
    .content-section {
      padding: 5rem 0;
      position: relative;
    }
    .section-heading-wrap {
      margin-bottom: 3.25rem;
    }
    .section-eyebrow {
      font-size: 0.8125rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.12em;
      color: var(--accent);
      margin-bottom: 0.5rem;
      display: inline-block;
    }
    .section-title {
      font-size: 2.125rem;
      line-height: 1.25;
      margin-bottom: 0.85rem;
    }
    .section-desc {
      color: var(--text-muted);
      font-size: 1rem;
      max-width: 760px;
      margin: 0 auto;
    }

    /* Hero: Whitepaper Lead Gen */
    .hero-banner {
      background: linear-gradient(135deg, rgba(15, 23, 42, 0.95) 0%, rgba(30, 41, 59, 0.9) 100%),
                  url('/assets/images/bb2b06c00a453a34.jpg') center/cover no-repeat;
      color: #FFFFFF;
      padding: 5.5rem 0 4.5rem;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }
    .hero-h1 {
      font-size: 2.75rem;
      font-weight: 800;
      line-height: 1.2;
      color: #FFFFFF;
      margin-bottom: 1.25rem;
    }
    .hero-summary {
      font-size: 1.05rem;
      line-height: 1.7;
      color: #CBD5E1;
      margin-bottom: 1.75rem;
    }
    .lead-download-card {
      background: rgba(255, 255, 255, 0.04);
      border: 1px solid rgba(255, 255, 255, 0.12);
      border-radius: var(--radius-card);
      padding: 1.75rem;
      box-shadow: 0 16px 36px rgba(0, 0, 0, 0.35);
      backdrop-filter: blur(8px);
    }
    .doc-preview-badge {
      font-size: 0.75rem;
      font-weight: 700;
      color: #A7F3D0;
      background: rgba(16, 185, 129, 0.15);
      border: 1px solid rgba(16, 185, 129, 0.3);
      padding: 0.25rem 0.65rem;
      border-radius: 4px;
      display: inline-block;
    }

    /* Standard Cards */
    .custom-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      border: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-subtle);
      padding: 1.75rem;
      height: 100%;
      transition: transform 0.2s ease, box-shadow 0.2s ease;
    }
    .custom-card:hover {
      transform: translateY(-3px);
      box-shadow: 0 12px 28px -4px rgba(15, 23, 42, 0.08);
    }

    /* Dark Panel Component */
    .dark-section {
      background-color: var(--primary);
      color: #FFFFFF;
    }
    .dark-section .section-title {
      color: #FFFFFF;
    }
    .dark-section .section-desc {
      color: #94A3B8;
    }
    .dark-metric-card {
      background: var(--neutral-dark);
      border: 1px solid rgba(255, 255, 255, 0.08);
      border-radius: var(--radius-card);
      padding: 1.75rem;
    }
    .metric-value {
      font-family: var(--font-mono);
      font-size: 2.25rem;
      font-weight: 700;
      color: var(--accent);
      line-height: 1;
      margin-bottom: 0.5rem;
    }

    /* Comparison Table */
    .compare-table {
      width: 100%;
      border-collapse: separate;
      border-spacing: 0;
      background: #FFFFFF;
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-subtle);
    }
    .compare-table th, .compare-table td {
      padding: 1.15rem 1.35rem;
      text-align: left;
    }
    .compare-table thead th {
      background: #F1F5F9;
      color: var(--primary);
      font-weight: 700;
      border-bottom: 1px solid var(--border-subtle);
    }
    .compare-table tbody tr:not(:last-child) td {
      border-bottom: 1px solid #F1F5F9;
    }
    .compare-table tbody tr:hover {
      background-color: #F8FAFC;
    }

    /* Timeline Component */
    .timeline-wrap {
      position: relative;
      padding-left: 2rem;
      border-left: 2px solid #E2E8F0;
    }
    .timeline-node {
      position: relative;
      margin-bottom: 2.25rem;
    }
    .timeline-node::before {
      content: '';
      position: absolute;
      left: -2.4rem;
      top: 0.35rem;
      width: 14px;
      height: 14px;
      border-radius: 50%;
      background: var(--accent);
      border: 3px solid #FFFFFF;
      box-shadow: 0 0 0 2px var(--accent);
    }

    /* FAQ Accordion Styling */
    .accordion-item {
      border: 1px solid var(--border-subtle);
      margin-bottom: 0.75rem;
      border-radius: var(--radius-card) !important;
      overflow: hidden;
    }
    .accordion-button {
      font-weight: 700;
      color: var(--primary);
      background-color: #FFFFFF;
      padding: 1.2rem 1.35rem;
    }
    .accordion-button:not(.collapsed) {
      color: #065F46;
      background-color: #ECFDF5;
      box-shadow: none;
    }
    .accordion-button:focus {
      box-shadow: none;
      border-color: rgba(16, 185, 129, 0.25);
    }
    .accordion-body {
      color: #475569;
      font-size: 0.9375rem;
      line-height: 1.7;
      background-color: #FFFFFF;
    }

    /* Footer */
    .site-footer {
      background: #0B0F17;
      color: #94A3B8;
      font-size: 0.875rem;
      padding: 4.5rem 0 2rem;
      border-top: 1px solid rgba(255, 255, 255, 0.08);
    }
    .footer-title {
      color: #FFFFFF;
      font-size: 0.9375rem;
      font-weight: 700;
      margin-bottom: 1.15rem;
      letter-spacing: 0.02em;
    }
    .footer-links {
      list-style: none;
      padding: 0;
      margin: 0;
    }
    .footer-links li {
      margin-bottom: 0.65rem;
    }
    .footer-links a:hover {
      color: var(--accent);
    }
    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.07);
      margin-top: 3.5rem;
      padding-top: 1.75rem;
      font-size: 0.8125rem;
      color: #64748B;
    }

    /* Responsive Adjustments */
    @media (max-width: 991.98px) {
      .hero-h1 { font-size: 2.15rem; }
      .section-title { font-size: 1.85rem; }
      .content-section { padding: 4rem 0; }
      .nav-search-box { display: none; }
    }