:root {
  color-scheme: dark;
  --bg: #111214;
  --panel: #17191d;
  --border: rgba(255, 255, 255, 0.08);
  --text: #e7ebf2;
  --muted: #a9b3c2;
  --accent: #67a7ff;
  --accent-soft: rgba(103, 167, 255, 0.14);
  --accent-border: rgba(103, 167, 255, 0.24);
  --shadow: 0 24px 64px rgba(0, 0, 0, 0.32);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(circle at top, rgba(103, 167, 255, 0.08), transparent 32%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.02), transparent 30%),
    var(--bg);
  color: var(--text);
  font-family: Inter, system-ui, sans-serif;
}

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

a:hover {
  text-decoration: underline;
}

.shell {
  max-width: 1220px;
  margin: 0 auto;
  padding: 28px 24px 56px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: 14px;
  font-weight: 700;
}

.brand img {
  width: 18px;
  height: 18px;
}

.topbar-links {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.04);
  color: var(--muted);
  font-size: 12px;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.65fr);
  gap: 20px;
  margin-bottom: 20px;
}

.hero-card,
.summary-card,
.article-card,
.toc-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.hero-card {
  padding: 28px;
}

.summary-card,
.toc-card {
  padding: 22px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 12px;
  border-radius: 999px;
  border: 1px solid var(--accent-border);
  background: var(--accent-soft);
  color: #b8d5ff;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.title {
  margin: 18px 0 0;
  font-size: clamp(34px, 5vw, 52px);
  line-height: 1.05;
}

.lead {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.75;
  max-width: 780px;
}

.meta-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 24px;
}

.meta-item {
  border-radius: 16px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.03);
  padding: 16px;
}

.meta-label {
  display: block;
  color: #7f8a9a;
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.meta-value {
  display: block;
  margin-top: 8px;
  color: var(--text);
  font-size: 14px;
  line-height: 1.55;
}

.layout {
  display: grid;
  grid-template-columns: minmax(0, 280px) minmax(0, 1fr);
  gap: 20px;
  align-items: start;
}

.toc-card {
  position: sticky;
  top: 24px;
}

.toc-title,
.summary-title {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #8f98a8;
}

.toc-links,
.summary-list {
  display: grid;
  gap: 10px;
  margin-top: 14px;
}

.toc-links a,
.summary-list a {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}

.summary-note {
  margin-top: 16px;
  padding: 14px 16px;
  border-radius: 16px;
  border: 1px solid var(--accent-border);
  background: var(--accent-soft);
  color: #dce9ff;
  font-size: 13px;
  line-height: 1.65;
}

.article-card {
  padding: 30px;
}

.section + .section {
  margin-top: 30px;
  padding-top: 30px;
  border-top: 1px solid var(--border);
}

.section h2 {
  margin: 0 0 14px;
  font-size: 24px;
  color: #fff;
}

.section p {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.8;
}

.section ul {
  margin: 14px 0 0;
  padding-left: 20px;
  color: var(--muted);
}

.section li {
  margin: 8px 0;
  line-height: 1.75;
}

.section strong {
  color: #f5f7fb;
}

.callout {
  margin-top: 16px;
  padding: 16px 18px;
  border-radius: 18px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.03);
}

.callout.warning {
  border-color: rgba(246, 173, 173, 0.24);
  background: rgba(246, 173, 173, 0.08);
  color: #ffe4e4;
}

.callout.success {
  border-color: rgba(154, 230, 180, 0.22);
  background: rgba(154, 230, 180, 0.08);
  color: #dffff0;
}

.footer {
  margin-top: 24px;
  border-top: 1px solid var(--border);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 2px 0;
  color: #97a2b2;
  font-size: 13px;
  flex-wrap: wrap;
}

.footer-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

@media (max-width: 980px) {
  .hero,
  .layout {
    grid-template-columns: 1fr;
  }

  .toc-card {
    position: static;
  }
}

@media (max-width: 640px) {
  .shell {
    padding: 18px 14px 36px;
  }

  .hero-card,
  .summary-card,
  .article-card,
  .toc-card {
    border-radius: 20px;
    padding: 20px;
  }

  .meta-grid {
    grid-template-columns: 1fr;
  }
}