:root {
  --color-primary-ink: #172033;
  --color-body-text: #2F3746;
  --color-muted-text: #667085;
  --color-warm-paper: #FAF7F2;
  --color-card-bg: #FFFFFF;
  --color-soft-border: #E8E1D8;
  --color-accent: #C65A3A;
  --color-accent-soft: #FFF0E8;
  --color-dark-bg: #111827;
  --color-cta-hover: #A9482E;
  --font-heading: "Manrope", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-body: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", "SFMono-Regular", Consolas, monospace;
  --radius-card: 16px;
  --radius-button: 10px;
  --content-width: 760px;
  --container-width: 1160px;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--color-warm-paper);
  color: var(--color-body-text);
  font-family: var(--font-body);
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  background: var(--color-warm-paper);
  color: var(--color-body-text);
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: var(--color-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--color-cta-hover);
}

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

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px max(20px, calc((100vw - var(--container-width)) / 2));
  border-bottom: 1px solid var(--color-soft-border);
  background: rgba(250, 247, 242, 0.96);
}

.brand-link {
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
}

.site-nav {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 8px 18px;
  font-family: var(--font-heading);
  font-size: 14px;
  font-weight: 700;
}

.site-nav a {
  color: var(--color-primary-ink);
  text-decoration: none;
}

.site-nav a:hover {
  color: var(--color-accent);
}

.site-nav .nav-cta {
  padding: 9px 12px;
  border: 1px solid var(--color-soft-border);
  border-radius: var(--radius-button);
  background: var(--color-card-bg);
  color: var(--color-accent);
}

.intro-section,
.page-header {
  padding: 72px 0 36px;
}

.intro-section .container,
.page-header .container {
  max-width: 850px;
  margin-left: max(20px, calc((100vw - var(--container-width)) / 2));
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--color-accent);
  font-family: var(--font-heading);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin: 0;
  color: var(--color-primary-ink);
  font-family: var(--font-heading);
  line-height: 1.12;
}

.intro-section h1,
.page-header h1 {
  max-width: 820px;
  font-size: clamp(2.25rem, 5vw, 4rem);
  letter-spacing: 0;
}

.intro-section p:not(.eyebrow),
.page-header p:not(.eyebrow) {
  max-width: 720px;
  margin: 20px 0 0;
  color: var(--color-body-text);
  font-size: 19px;
  line-height: 1.65;
}

.content-section {
  padding: 34px 0 64px;
}

.content-section.compact {
  padding-top: 0;
}

.section-heading {
  margin-bottom: 24px;
}

.section-heading h2 {
  font-size: clamp(1.65rem, 3vw, 2.25rem);
}

.article-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.article-card {
  display: flex;
  min-height: 260px;
  flex-direction: column;
  gap: 16px;
  padding: 24px;
  border: 1px solid var(--color-soft-border);
  border-radius: var(--radius-card);
  background: var(--color-card-bg);
  color: var(--color-body-text);
  text-decoration: none;
  transition: border-color 160ms ease, transform 160ms ease;
}

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

.article-card:hover h2 {
  text-decoration: underline;
  text-decoration-color: var(--color-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

.category-tag {
  display: inline-flex;
  width: max-content;
  align-items: center;
  padding: 6px 10px;
  border-radius: 999px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  font-family: var(--font-heading);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.article-card h2 {
  font-size: 24px;
  line-height: 1.18;
}

.article-card p {
  margin: 0;
  color: var(--color-muted-text);
  font-size: 16px;
  line-height: 1.6;
}

.card-meta {
  margin-top: auto;
  color: var(--color-muted-text);
  font-size: 14px;
  font-weight: 600;
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.category-card {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 18px;
  border: 1px solid var(--color-soft-border);
  border-radius: var(--radius-card);
  background: var(--color-card-bg);
  color: var(--color-primary-ink);
  text-decoration: none;
}

.category-card strong {
  font-family: var(--font-heading);
}

.category-card span {
  color: var(--color-muted-text);
  white-space: nowrap;
}

.category-card:hover {
  border-color: var(--color-accent);
  color: var(--color-primary-ink);
}

.article-shell {
  padding: 58px 20px 84px;
}

.article-layout {
  width: min(var(--content-width), 100%);
  margin: 0 auto;
}

.article-hero {
  padding-bottom: 34px;
  border-bottom: 1px solid var(--color-soft-border);
}

.article-hero h1 {
  margin-top: 18px;
  font-size: clamp(2.125rem, 6vw, 3.5rem);
  letter-spacing: 0;
}

.article-deck {
  margin: 20px 0 0;
  color: var(--color-body-text);
  font-size: 21px;
  line-height: 1.6;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-top: 18px;
  color: var(--color-muted-text);
  font-size: 14px;
  font-weight: 600;
}

.category-hub-link {
  margin: 16px 0 0;
  color: var(--color-muted-text);
  font-size: 15px;
}

.article-content {
  padding-top: 32px;
  font-size: 18px;
  line-height: 1.72;
}

.article-content h2 {
  margin-top: 48px;
  font-size: 34px;
}

.article-content h3 {
  margin-top: 32px;
  font-size: 24px;
}

.article-content p,
.article-content ul,
.article-content ol {
  margin: 18px 0 0;
}

.article-content li + li {
  margin-top: 8px;
}

.article-content code {
  font-family: var(--font-mono);
  font-size: 0.92em;
}

.toc-card {
  margin: 32px 0 44px;
  padding: 22px;
  border: 1px solid var(--color-soft-border);
  border-radius: var(--radius-card);
  background: var(--color-card-bg);
}

.toc-card h2 {
  margin: 0 0 12px;
  font-size: 20px;
}

.toc-card ul {
  display: grid;
  gap: 8px;
  margin: 0;
  padding-left: 20px;
}

.toc-card a {
  color: var(--color-primary-ink);
  font-size: 16px;
  font-weight: 650;
  text-decoration: none;
}

.toc-card a:hover {
  color: var(--color-accent);
}

.example-box,
.formula-box {
  margin: 24px 0 0;
  border: 1px solid var(--color-soft-border);
  border-radius: var(--radius-card);
}

.example-box {
  padding: 18px 22px;
  border-left: 4px solid var(--color-accent);
  background: var(--color-card-bg);
}

.example-box p {
  margin: 0;
}

.formula-box {
  overflow-x: auto;
  padding: 18px 20px;
  background: var(--color-accent-soft);
  color: var(--color-primary-ink);
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1.6;
  white-space: pre-wrap;
}

.related-articles {
  margin-top: 56px;
  padding-top: 34px;
  border-top: 1px solid var(--color-soft-border);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.related-card {
  display: grid;
  gap: 8px;
  padding: 18px;
  border: 1px solid var(--color-soft-border);
  border-radius: var(--radius-card);
  background: var(--color-card-bg);
  color: var(--color-primary-ink);
  text-decoration: none;
}

.related-card span {
  color: var(--color-accent);
  font-family: var(--font-heading);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.related-card strong {
  font-family: var(--font-heading);
  font-size: 18px;
  line-height: 1.3;
}

.related-card:hover {
  border-color: var(--color-accent);
  color: var(--color-primary-ink);
}

.freecopyaudit-cta {
  margin: 56px 0 0;
  padding: 28px;
  border: 1px solid var(--color-soft-border);
  border-radius: var(--radius-card);
  background: var(--color-accent-soft);
}

.freecopyaudit-cta h2 {
  max-width: 620px;
  font-size: clamp(1.55rem, 3vw, 2rem);
}

.freecopyaudit-cta p {
  max-width: 680px;
  margin: 14px 0 22px;
  font-size: 17px;
  line-height: 1.6;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 11px 18px;
  border-radius: var(--radius-button);
  background: var(--color-accent);
  color: #fff;
  font-family: var(--font-heading);
  font-size: 15px;
  font-weight: 800;
  text-decoration: none;
}

.button:hover {
  background: var(--color-cta-hover);
  color: #fff;
}

.site-footer {
  margin-top: 64px;
  padding: 46px 20px;
  background: var(--color-dark-bg);
  color: #fff;
}

.footer-inner {
  display: grid;
  width: min(var(--container-width), 100%);
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 36px;
  margin: 0 auto;
}

.site-footer h2 {
  margin-bottom: 14px;
  color: #fff;
  font-size: 15px;
}

.site-footer p,
.site-footer a {
  color: var(--color-soft-border);
  font-size: 14px;
  line-height: 1.65;
}

.site-footer a {
  display: block;
  margin-top: 8px;
  text-decoration: none;
}

.site-footer a:hover {
  color: #fff;
}

.copyright {
  margin-top: 20px;
}

@media (max-width: 920px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

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

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

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

@media (max-width: 640px) {
  .container {
    width: min(100% - 36px, var(--container-width));
  }

  .site-header {
    padding: 16px 18px;
  }

  .site-nav {
    justify-content: flex-start;
    gap: 8px 14px;
  }

  .intro-section,
  .page-header {
    padding: 48px 0 26px;
  }

  .intro-section .container,
  .page-header .container {
    margin: 0 auto;
  }

  .intro-section p:not(.eyebrow),
  .page-header p:not(.eyebrow) {
    font-size: 17px;
  }

  .article-grid,
  .category-grid,
  .related-grid,
  .footer-inner {
    grid-template-columns: 1fr;
  }

  .article-card {
    min-height: auto;
  }

  .article-shell {
    padding: 42px 20px 64px;
  }

  .article-content {
    font-size: 17px;
    line-height: 1.68;
  }

  .article-content h2 {
    font-size: 28px;
  }

  .article-content h3 {
    font-size: 22px;
  }

  .article-deck {
    font-size: 18px;
  }

  .freecopyaudit-cta {
    padding: 22px;
  }
}