:root {
  color-scheme: light;
  --surface: #ffffff;
  --surface-soft: #F8FAFC;
  --text-primary: #0F172A;
  --text-secondary: #475569;
  --border: #E2E8F0;
  --ink: #111827;
  --muted: #667085;
  --line: #d7dee8;
  --soft: #f3f6fb;
  --panel: #ffffff;
  --blue: #1d5fd1;
  --blue-dark: #1447a6;
  --green: #067647;
  --orange: #c2410c;
  --shadow: 0 10px 26px rgba(16, 24, 40, .07);
}
* { box-sizing: border-box; }
html { min-height: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: Arial, Helvetica, sans-serif;
  color: var(--ink);
  background: var(--soft);
}
a { color: var(--blue); text-decoration: none; }
a:hover { color: var(--blue-dark); text-decoration: underline; }
.site-header {
  background: var(--panel);
  border-bottom: 1px solid var(--line);
  box-shadow: 0 1px 0 rgba(16, 24, 40, .02);
}
.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 20px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 30px;
  flex-wrap: wrap;
  color: var(--ink);
}
.brand-logo {
  width: min(300px, 70vw);
  max-height: 76px;
  object-fit: contain;
  display: block;
}
.brand-copy {
  min-width: 240px;
}
.brand-title {
  margin: 0 0 6px;
  color: var(--ink);
  font-size: 28px;
  line-height: 1.15;
  font-weight: 800;
  letter-spacing: 0;
}
.brand-meta {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.4;
}
.nav {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 13px;
  font-weight: 800;
}
.nav a { color: #344054; }
.nav .primary {
  color: #fff;
  background: var(--blue);
  padding: 13px 16px;
  border-radius: 6px;
  min-width: 96px;
  text-align: center;
}
.nav .primary:hover { background: var(--blue-dark); text-decoration: none; }
.hero {
  max-width: 1200px;
  margin: 0 auto;
  padding: 44px 28px 20px;
}
.eyebrow {
  color: var(--blue);
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: .06em;
  margin: 0 0 10px;
}
h1 {
  max-width: 880px;
  margin: 0;
  font-size: clamp(32px, 5vw, 56px);
  line-height: 1.05;
  letter-spacing: 0;
}
.lead {
  max-width: 780px;
  margin: 16px 0 0;
  color: #475467;
  font-size: 18px;
  line-height: 1.55;
}
.main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 22px 28px 56px;
}
.grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}
.card {
  min-height: 184px;
  padding: 18px;
  background: var(--panel);
  border: 1px solid #e4e9f0;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(16, 24, 40, .04);
}
.card:hover {
  border-color: #b2ccff;
  box-shadow: var(--shadow);
  text-decoration: none;
}
.card h2 {
  margin: 0 0 8px;
  color: var(--ink);
  font-size: 19px;
  line-height: 1.25;
}
.card p {
  margin: 0 0 14px;
  color: #526071;
  font-size: 14px;
  line-height: 1.5;
}
.intro-panel {
  margin: 0 0 18px;
  padding: 20px;
  background: #fff;
  border: 1px solid #e4e9f0;
  border-radius: 8px;
}
.intro-panel h2 {
  margin: 0 0 8px;
  font-size: 22px;
}
.intro-panel p {
  margin: 0;
  max-width: 920px;
  color: #475467;
  font-size: 16px;
  line-height: 1.65;
}
.tag {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  padding: 3px 8px;
  font-size: 11px;
  font-weight: 800;
  color: #1849a9;
  background: #eef4ff;
  border: 1px solid #c7d7fe;
}
.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 22px;
  align-items: start;
}
.article {
  background: var(--panel);
  border: 1px solid #e4e9f0;
  border-radius: 8px;
  box-shadow: var(--shadow);
  padding: 28px;
}
.article h1 {
  font-size: clamp(30px, 4vw, 46px);
}
.article h2 {
  margin: 30px 0 10px;
  font-size: 22px;
  line-height: 1.25;
}
.article p,
.article li {
  color: #344054;
  font-size: 16px;
  line-height: 1.65;
}
.article ul,
.article ol { padding-left: 22px; }
.source-list {
  margin-top: 10px;
}
.source-list a {
  font-weight: 700;
}
.article code,
.article pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}
.article pre {
  overflow: auto;
  padding: 14px;
  border-radius: 8px;
  color: #f9fafb;
  background: #111827;
  line-height: 1.55;
}
.toc {
  position: sticky;
  top: 18px;
  background: var(--panel);
  border: 1px solid #e4e9f0;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(16, 24, 40, .04);
  padding: 16px;
}
.toc strong {
  display: block;
  margin-bottom: 10px;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .04em;
  color: #344054;
}
.toc a {
  display: block;
  padding: 6px 0;
  color: #526071;
  font-size: 13px;
  font-weight: 700;
}
.callout {
  margin: 20px 0;
  padding: 14px 16px;
  border-radius: 8px;
  border: 1px solid #b7efc8;
  background: #ecfdf3;
  color: #05603a;
  font-weight: 700;
}
.warning {
  border-color: #fdba74;
  background: #fff7ed;
  color: var(--orange);
}
.site-footer {
  width: 100%;
  margin-top: auto;
  padding: 0 28px 30px;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.6;
}
.footer-shell {
  max-width: 1180px;
  width: 100%;
  margin: 0 auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: 0 4px 16px rgba(15, 23, 42, .04);
  overflow: hidden;
}
.footer-main {
  display: grid;
  grid-template-columns: 1.5fr 1fr .75fr;
  gap: 40px;
  padding: 28px 32px;
  text-align: left;
}
.footer-brand-title {
  margin: 0 0 10px;
  color: var(--text-primary);
  font-size: 18px;
  line-height: 1.25;
  font-weight: 700;
}
.footer-copy {
  max-width: 560px;
  margin: 0;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.6;
}
.footer-heading {
  margin: 0 0 12px;
  color: #334155;
  font-size: 12px;
  line-height: 1.2;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
}
.footer-links {
  display: grid;
  gap: 7px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-secondary);
}
.footer-link-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(90px, 1fr));
  gap: 24px;
}
.footer-links a {
  color: #1D4ED8;
  font-weight: 650;
  text-decoration: none;
}
.footer-links a:hover {
  text-decoration: underline;
}
.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 15px 32px;
  border-top: 1px solid var(--border);
  background: var(--surface-soft);
  color: var(--text-secondary);
  font-size: 13px;
}
.footer-bottom a {
  color: #1D4ED8;
  font-weight: 650;
  text-decoration: none;
}
.footer-bottom a:hover {
  text-decoration: underline;
}
@media (max-width: 900px) {
  .header-inner,
  .hero,
  .main,
  .site-footer { padding-left: 16px; padding-right: 16px; }
  .header-inner { align-items: flex-start; flex-direction: column; }
  .grid { grid-template-columns: 1fr; }
  .article-layout { grid-template-columns: 1fr; }
  .toc { position: static; }
  .article { padding: 20px; }
  .footer-main {
    grid-template-columns: 1fr;
    gap: 18px;
    padding: 20px;
  }
  .footer-bottom {
    align-items: flex-start;
    flex-direction: column;
    padding: 13px 20px;
  }
}