:root {
  --ink: #172027;
  --muted: #5f6972;
  --line: #dbe2e8;
  --paper: #ffffff;
  --soft: #f5f7f8;
  --accent: #2f6f73;
  --accent-deep: #1d4d55;
  --warm: #b7793d;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.8;
}

a {
  color: inherit;
}

.site-header {
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.96);
  position: sticky;
  top: 0;
  z-index: 10;
}

.header-inner,
.hero-inner,
.main-layout,
.footer-inner {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 14px 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex: 0 0 auto;
}

.brand-mark {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border: 1px solid var(--accent);
  color: var(--accent-deep);
  font-weight: 700;
}

.brand strong,
.brand small {
  display: block;
}

.brand small {
  color: var(--muted);
  font-size: 12px;
  line-height: 1.3;
}

.site-nav {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  white-space: nowrap;
  padding-bottom: 2px;
}

.site-nav a {
  text-decoration: none;
  color: var(--muted);
  padding: 8px 10px;
  border-bottom: 2px solid transparent;
  font-size: 14px;
}

.site-nav a[aria-current="page"],
.site-nav a:hover {
  color: var(--accent-deep);
  border-bottom-color: var(--accent);
}

.hero {
  background:
    linear-gradient(120deg, rgba(47, 111, 115, 0.10), rgba(183, 121, 61, 0.08)),
    var(--soft);
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  padding: 62px 0 50px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent-deep);
  font-weight: 700;
  letter-spacing: 0;
}

h1 {
  margin: 0;
  font-size: clamp(32px, 6vw, 54px);
  line-height: 1.18;
  letter-spacing: 0;
}

.lead {
  max-width: 760px;
  margin: 22px 0 0;
  color: #34414b;
  font-size: 18px;
}

.main-layout {
  padding: 44px 0 64px;
}

.article {
  max-width: 920px;
}

.content-section {
  padding: 28px 0;
  border-bottom: 1px solid var(--line);
}

.content-section:first-child {
  padding-top: 0;
}

h2 {
  margin: 0 0 14px;
  font-size: 24px;
  line-height: 1.35;
  letter-spacing: 0;
}

p {
  margin: 0 0 14px;
}

p:last-child {
  margin-bottom: 0;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  padding-top: 32px;
}

.topic-card {
  min-height: 190px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
  text-decoration: none;
  background: #fff;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.topic-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.topic-card span {
  display: block;
  color: var(--warm);
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 8px;
}

.topic-card strong {
  display: block;
  line-height: 1.45;
  margin-bottom: 8px;
}

.topic-card p {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.7;
}

.related {
  margin-top: 32px;
  padding: 24px 0 0;
}

.related-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.related-links a {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px 14px;
  text-decoration: none;
  color: var(--accent-deep);
  background: var(--soft);
}

.site-footer {
  border-top: 1px solid var(--line);
  background: #f7f9fa;
  color: var(--muted);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 28px 0;
}

.footer-inner strong {
  color: var(--ink);
}

.footer-inner nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: flex-end;
}

.footer-inner nav a {
  color: var(--accent-deep);
  text-decoration: none;
}

.copyright {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 0 0 24px;
  font-size: 13px;
}

@media (max-width: 880px) {
  .header-inner {
    align-items: flex-start;
    flex-direction: column;
  }

  .site-nav {
    width: 100%;
  }

  .hero-inner {
    padding: 44px 0 38px;
  }

  .topic-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-inner {
    flex-direction: column;
  }

  .footer-inner nav {
    justify-content: flex-start;
  }
}

@media (max-width: 560px) {
  .header-inner,
  .hero-inner,
  .main-layout,
  .footer-inner,
  .copyright {
    width: min(100% - 24px, 1120px);
  }

  .brand small {
    display: none;
  }

  .lead {
    font-size: 16px;
  }

  h2 {
    font-size: 21px;
  }

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

  .topic-card {
    min-height: 0;
  }
}