:root {
  --ink: #16191b;
  --soft-ink: #384047;
  --muted: #68737c;
  --faint: #eef1f2;
  --line: #d7dee2;
  --paper: #ffffff;
  --ground: #fafafa;
  --accent: #1b6f72;
  --accent-2: #8d4f38;
  --accent-3: #345f8d;
  --max: 1180px;
  color-scheme: light;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

a {
  color: inherit;
  text-decoration: none;
}

p {
  margin: 0;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid var(--line);
  background: rgba(250, 250, 250, 0.92);
  backdrop-filter: blur(18px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  width: min(var(--max), calc(100% - 40px));
  min-height: 72px;
  margin: 0 auto;
}

.brand {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 23px;
  letter-spacing: 0;
}

.brand span {
  color: var(--muted);
  font-family: inherit;
  font-size: 16px;
}

.site-nav {
  display: flex;
  gap: 2px;
}

.site-nav a {
  padding: 9px 11px;
  color: var(--soft-ink);
  border-radius: 6px;
  font-size: 14px;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  background: var(--faint);
}

.nav-toggle {
  display: none;
}

.page {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: clamp(42px, 7vw, 108px);
  padding: clamp(74px, 11vw, 138px) 0 70px;
  border-bottom: 1px solid var(--line);
}

.eyebrow {
  margin: 0 0 18px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 760;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin: 0;
  letter-spacing: 0;
}

h1,
h2 {
  font-family: Georgia, "Times New Roman", serif;
  font-weight: 500;
}

h1 {
  max-width: 860px;
  font-size: clamp(48px, 8vw, 94px);
  line-height: 0.98;
}

h2 {
  font-size: clamp(34px, 4.8vw, 58px);
  line-height: 1.04;
}

h3 {
  font-size: 20px;
  line-height: 1.25;
}

.lede {
  max-width: 780px;
  margin-top: 28px;
  color: var(--soft-ink);
  font-size: clamp(20px, 2.5vw, 28px);
  line-height: 1.42;
}

.hero-note {
  align-self: end;
  padding-top: 18px;
  border-top: 2px solid var(--ink);
  color: var(--muted);
  font-size: 15px;
  line-height: 1.6;
}

.hero-note strong {
  display: block;
  margin-bottom: 12px;
  color: var(--ink);
  font-size: 24px;
  font-family: Georgia, "Times New Roman", serif;
  font-weight: 500;
}

.section {
  padding: clamp(58px, 8vw, 94px) 0;
  border-bottom: 1px solid var(--line);
}

.section-grid {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: clamp(32px, 7vw, 92px);
}

.section-kicker {
  color: var(--muted);
  font-size: 13px;
  font-weight: 760;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.prose {
  display: grid;
  gap: 18px;
  color: var(--soft-ink);
  font-size: 18px;
  line-height: 1.68;
}

.fine-print {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.55;
}

.link-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.text-link,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  border-radius: 6px;
  font-weight: 720;
}

.button {
  padding: 10px 15px;
  color: #fff;
  background: var(--ink);
}

.button.secondary {
  color: var(--ink);
  border: 1px solid var(--line);
  background: transparent;
}

.text-link {
  color: var(--accent);
}

.paper-list,
.post-list,
.method-list {
  display: grid;
  gap: 1px;
  border: 1px solid var(--line);
  background: var(--line);
}

.paper-item,
.post-item,
.method-item {
  display: grid;
  grid-template-columns: 170px minmax(0, 1fr) auto;
  gap: 24px;
  align-items: start;
  padding: 24px;
  background: var(--paper);
}

.post-item {
  grid-template-columns: 180px minmax(0, 1fr);
}

.method-item {
  grid-template-columns: 150px minmax(0, 1fr);
}

.meta {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.55;
}

.meta strong {
  display: block;
  color: var(--accent-2);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.paper-item p,
.post-item p,
.method-item p {
  margin-top: 9px;
  color: var(--muted);
  line-height: 1.58;
}

.paper-actions {
  display: flex;
  gap: 8px;
  white-space: nowrap;
}

.quiet-panel {
  padding: 28px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin-top: 34px;
  border: 1px solid var(--line);
  background: var(--line);
}

.stat {
  padding: 22px;
  background: var(--paper);
}

.stat strong {
  display: block;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 34px;
  font-weight: 500;
}

.stat span {
  color: var(--muted);
  font-size: 14px;
}

.page-title {
  padding: clamp(58px, 9vw, 104px) 0 44px;
  border-bottom: 1px solid var(--line);
}

.page-title .lede {
  max-width: 880px;
}

.blog-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 46px;
  align-items: start;
}

.article {
  max-width: 820px;
}

.article-wide {
  max-width: 980px;
}

.article-header {
  padding: clamp(56px, 9vw, 96px) 0 34px;
  border-bottom: 1px solid var(--line);
}

.article-header h1 {
  max-width: 980px;
  font-size: clamp(42px, 6vw, 76px);
}

.article-meta {
  margin-bottom: 18px;
  color: var(--accent-2);
  font-size: 12px;
  font-weight: 760;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

.article-body {
  display: grid;
  gap: 22px;
  padding: 46px 0 80px;
  color: var(--soft-ink);
  font-size: 19px;
  line-height: 1.72;
}

.article-body h2 {
  margin-top: 26px;
  font-size: 34px;
}

.chart-panel {
  margin: 16px 0 28px;
  padding: 20px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.chart-panel h3 {
  margin-bottom: 6px;
}

.chart-panel p {
  margin-bottom: 18px;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.5;
}

.chart-box {
  height: 330px;
}

.chart-panel.coefplot {
  padding: 24px;
}

.chart-panel.coefplot .chart-box {
  height: 470px;
}

.sidebar {
  position: sticky;
  top: 98px;
  display: grid;
  gap: 16px;
}

.small-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.small-list li {
  padding: 12px 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  line-height: 1.5;
}

.site-footer {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
  padding: 30px 0 42px;
  color: var(--muted);
  font-size: 14px;
}

code {
  padding: 2px 5px;
  border-radius: 4px;
  background: var(--faint);
  font-size: 0.92em;
}

@media (max-width: 920px) {
  .hero,
  .section-grid,
  .blog-layout,
  .paper-item,
  .post-item,
  .method-item {
    grid-template-columns: 1fr;
  }

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

  .paper-actions {
    flex-wrap: wrap;
  }

  .sidebar {
    position: static;
  }
}

@media (max-width: 760px) {
  .header-inner,
  .page,
  .site-footer {
    width: min(100% - 28px, var(--max));
  }

  .nav-toggle {
    display: inline-grid;
    place-items: center;
    width: 40px;
    height: 40px;
    border: 1px solid var(--line);
    border-radius: 6px;
    background: transparent;
  }

  .nav-toggle::before {
    content: "Menu";
    color: var(--soft-ink);
    font-size: 13px;
  }

  .site-nav {
    position: absolute;
    top: 72px;
    right: 14px;
    left: 14px;
    display: none;
    flex-direction: column;
    padding: 10px;
    border: 1px solid var(--line);
    background: var(--paper);
  }

  .site-nav.open {
    display: flex;
  }

  .brand {
    font-size: 20px;
  }

  .brand span {
    display: none;
  }

  .chart-panel {
    padding: 16px;
  }

  .chart-panel.coefplot .chart-box {
    height: 560px;
  }
}