:root {
  --bg: #F4F0E8;
  --surface: #FFFDF8;
  --surface-alt: #E7E0D2;
  --text: #1E2A33;
  --muted: #66717A;
  --accent: #0F7C6B;
  --accent-alt: #C65D2E;
  --line: #B9B1A2;
  --line-strong: rgba(30, 42, 51, 0.22);
  --line-soft: rgba(185, 177, 162, 0.55);
  --shadow-soft: none;
  --shadow-lifted: 0 1px 0 rgba(30,42,51,0.06), 0 0 0 1px rgba(185,177,162,0.7);
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 8px;
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 64px;
  --space-9: 96px;
  --container: min(1280px, calc(100vw - 48px));
  --reading: 70ch;
  --ui-family: 'IBM Plex Sans', 'Segoe UI', Arial, sans-serif;
  --body-family: 'Source Serif 4', Georgia, serif;
  --display-family: Fraunces, 'Iowan Old Style', Georgia, serif;
  --step--1: clamp(0.83rem, 0.8rem + 0.1vw, 0.92rem);
  --step-0: clamp(1rem, 0.96rem + 0.2vw, 1.08rem);
  --step-1: clamp(1.15rem, 1.06rem + 0.4vw, 1.35rem);
  --step-2: clamp(1.4rem, 1.2rem + 0.9vw, 1.8rem);
  --step-3: clamp(1.8rem, 1.45rem + 1.6vw, 2.7rem);
  --step-4: clamp(2.3rem, 1.7rem + 2.7vw, 4.2rem);
  --step-5: clamp(3rem, 2rem + 4vw, 5.4rem);
  --grid-gap: var(--space-6);
  --header-height: 72px;
  --anchor-offset: 96px;
  --texture: radial-gradient(circle at 20% 20%, rgba(30,42,51,0.025) 0, transparent 42%), radial-gradient(circle at 80% 0%, rgba(198,93,46,0.02) 0, transparent 35%), linear-gradient(transparent, transparent);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--body-family);
  font-size: var(--step-0);
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  text-rendering: optimizeLegibility;
}

a {
  color: inherit;
  text-decoration-color: rgba(15,124,107,0.55);
  text-underline-offset: 0.16em;
}

a:hover {
  text-decoration-color: var(--accent);
}

img,
svg,
picture {
  max-width: 100%;
  display: block;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

::selection {
  background: rgba(15,124,107,0.18);
}

main,
section,
article,
[id] {
  scroll-margin-top: var(--anchor-offset);
}

h1,
h2,
h3,
h4 {
  margin: 0 0 var(--space-4);
  line-height: 1.05;
  color: var(--text);
}

h1,
h2,
.hero-title,
.section-title {
  font-family: var(--display-family);
  letter-spacing: -0.02em;
}

h3,
h4 {
  font-family: var(--ui-family);
  letter-spacing: 0.01em;
}

p,
ul,
ol,
blockquote,
table {
  margin: 0 0 var(--space-5);
}

ul,
ol {
  padding-left: 1.2em;
}

hr,
.section-rule,
.footer-rule,
.nav-divider {
  border: 0;
  border-top: 1px solid var(--line);
}

.site-shell {
  min-height: 100vh;
  position: relative;
}

.site-shell::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.18;
  background-image: var(--texture);
  mix-blend-mode: multiply;
}

.container {
  width: var(--container);
  margin-inline: auto;
}

.page-grid,
.content-grid,
.chapter-grid,
.hero-grid,
.rail-layout,
.split-layout,
.two-up,
.three-up,
.footer-grid,
.facts-grid,
.comparison-grid {
  display: grid;
  gap: var(--grid-gap);
}

.page-grid {
  gap: var(--space-8);
}

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

.text-measure,
.lede,
.main-column > * {
  max-width: var(--reading);
}

.lede {
  font-size: var(--step-1);
  line-height: 1.55;
}

.eyebrow-code,
.coord-label,
.inline-label,
.section-kicker,
.hero-meta,
.header-meta,
.caption,
.data-note,
.criteria-label,
.table-caption,
.table-note,
.margin-note,
.brandmark,
.anchor-link,
.nav-link,
.footer-note,
.footer-meta,
.breadcrumb-trail,
.chapter-marker {
  font-family: var(--ui-family);
}

.eyebrow-code,
.coord-label,
.inline-label,
.section-kicker,
.chapter-marker {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.74rem;
  font-weight: 600;
}

.eyebrow-code::before,
.coord-label::before,
.section-kicker::before,
.chapter-marker::before {
  content: '';
  inline-size: 18px;
  block-size: 1px;
  background: currentColor;
}

.route-line,
.guide-dots,
.hero-trace,
.hero-gesture {
  position: relative;
}

.route-line::after,
.text-link-arrow::after,
.anchor-link::after {
  content: '→';
  display: inline-block;
  margin-left: 0.45em;
  transition: transform 180ms ease;
}

.text-link-arrow:hover::after,
.anchor-link:hover::after,
.text-link-arrow:focus-visible::after,
.anchor-link:focus-visible::after {
  transform: translateX(3px);
}

.guide-dots::before {
  content: '';
  position: absolute;
  inset: auto 0 100% 0;
  height: 6px;
  background-image: radial-gradient(circle, var(--line) 1px, transparent 1.5px);
  background-size: 10px 6px;
  background-repeat: repeat-x;
  opacity: 0.75;
}

.paper-texture,
.tone-surface,
.tone-alt,
.tone-band,
.note-panel,
.route-panel,
.comparison-panel,
.fact-panel,
.quote-panel,
.image-panel,
.chapter-panel,
.callout-strip,
.metric-block,
.plan-panel,
.cta-band,
.chapter-band,
.table-wrap {
  position: relative;
  background: var(--surface);
}

.paper-texture::before,
.tone-surface::before,
.tone-alt::before,
.tone-band::before,
.chapter-band::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: var(--texture);
  opacity: 0.15;
  pointer-events: none;
}

.tone-alt,
.chapter-band,
.note-panel,
.fact-panel,
.metric-block {
  background: var(--surface-alt);
}

.tone-band,
.cta-band,
.callout-strip {
  background: linear-gradient(180deg, rgba(231,224,210,0.85), rgba(255,253,248,0.96));
}

.rule-stack > * + * {
  padding-top: var(--space-4);
  border-top: 1px solid var(--line-soft);
}

.asym-break {
  padding-block: var(--space-7);
  position: relative;
}

.asym-break::after {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  width: min(22vw, 180px);
  height: 3px;
  background: var(--accent-alt);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(10px);
  background: rgba(244,240,232,0.92);
  border-bottom: 1px solid rgba(185,177,162,0.9);
}

.topbar {
  min-height: var(--header-height);
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: var(--space-5);
  padding-block: var(--space-3);
}

.brand-lockup {
  display: inline-grid;
  gap: 2px;
  text-decoration: none;
}

.brandmark {
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 700;
}

.brand-lockup strong {
  font-family: var(--display-family);
  font-size: var(--step-1);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.primary-nav {
  justify-self: end;
}

.nav-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  margin: 0;
  padding: 0;
  align-items: center;
}

.nav-item {
  margin: 0;
}

.nav-link {
  text-decoration: none;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  padding: var(--space-2) 0;
  position: relative;
}

.nav-link::before {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: 2px;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.nav-link:hover::before,
.nav-link:focus-visible::before,
.nav-link-active::before {
  transform: scaleX(1);
}

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

.header-meta,
.breadcrumb-trail,
.footer-note,
.footer-meta,
.caption,
.data-note,
.table-note {
  color: var(--muted);
  font-size: var(--step--1);
  line-height: 1.45;
}

.breadcrumb-trail,
.anchor-nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  align-items: center;
}

.anchor-nav {
  border-block: 1px solid var(--line);
  padding-block: var(--space-3);
  position: sticky;
  top: var(--header-height);
  z-index: 30;
  background: rgba(244,240,232,0.94);
}

.anchor-link {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.86rem;
  letter-spacing: 0.02em;
}

.anchor-link.is-active {
  color: var(--text);
}

.nav-toggle {
  display: none;
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  font-family: var(--ui-family);
  font-size: 0.84rem;
}

.hero-spread {
  padding-block: var(--space-8) var(--space-7);
}

.hero-grid {
  grid-template-columns: minmax(0, 1.75fr) minmax(240px, 0.85fr);
  align-items: end;
  gap: var(--space-7);
}

.hero-main {
  position: relative;
}

.hero-title {
  font-size: var(--step-5);
  max-width: 12ch;
  margin-bottom: var(--space-4);
}

.hero-dek {
  font-size: var(--step-1);
  max-width: 42ch;
  color: var(--text);
}

.hero-rail,
.meta-rail,
.sticky-rail,
.side-column {
  align-self: start;
}

.hero-meta,
.meta-rail {
  display: grid;
  gap: var(--space-3);
}

.hero-gesture {
  margin-top: var(--space-5);
  min-height: 44px;
}

.hero-trace,
.route-line {
  min-height: 16px;
}

.hero-trace::before,
.route-line::before {
  content: '';
  display: block;
  width: min(100%, 460px);
  height: 16px;
  border-top: 2px solid var(--accent);
  border-right: 2px solid var(--accent);
  border-radius: 0 14px 0 0;
  position: relative;
}

.hero-trace::after,
.route-line.node::before {
  content: '';
  position: absolute;
  top: -2px;
  right: max(0px, calc(100% - min(100%, 460px)));
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 5px rgba(15,124,107,0.12);
}

.chapter-band {
  padding: var(--space-7) 0;
  border-block: 1px solid var(--line);
}

.chapter-band .container,
.cta-band .container {
  position: relative;
  z-index: 1;
}

.section-title {
  font-size: var(--step-3);
  max-width: 16ch;
}

.section-dek {
  max-width: 56ch;
  color: var(--muted);
}

.chapter-grid {
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.chapter-panel,
.route-panel,
.note-panel,
.comparison-panel,
.fact-panel,
.quote-panel,
.image-panel,
.callout-strip,
.metric-block,
.plan-panel,
.table-wrap {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: var(--space-5);
  box-shadow: var(--shadow-lifted);
}

.route-panel,
.chapter-panel,
.note-panel,
.comparison-panel,
.image-panel {
  display: grid;
  gap: var(--space-3);
}

.route-panel h3,
.chapter-panel h3,
.comparison-panel h3,
.note-panel h3,
.fact-panel h3 {
  margin-bottom: var(--space-2);
  font-size: var(--step-1);
}

.route-panel {
  grid-column: span 6;
}

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

.three-up {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.split-layout,
.rail-layout {
  grid-template-columns: minmax(0, 1.55fr) minmax(260px, 0.7fr);
  align-items: start;
}

.main-column {
  min-width: 0;
}

.side-column,
.sticky-rail {
  position: sticky;
  top: calc(var(--header-height) + var(--space-5));
}

.margin-note {
  padding: var(--space-3) var(--space-4);
  border-left: 2px solid var(--accent-alt);
  background: rgba(231,224,210,0.55);
  color: var(--muted);
  max-width: 32ch;
}

.pull-quote,
blockquote {
  font-family: var(--display-family);
  font-size: var(--step-2);
  line-height: 1.25;
  padding-left: var(--space-5);
  border-left: 2px solid var(--accent-alt);
}

.caption {
  padding-top: var(--space-3);
  border-top: 1px solid var(--line-soft);
}

.facts-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-4);
}

.metric-block strong,
.fact-panel strong {
  display: block;
  font-family: var(--ui-family);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
  margin-bottom: var(--space-2);
}

.metric-block span,
.fact-panel span {
  font-size: var(--step-1);
  line-height: 1.2;
}

.table-wrap {
  overflow-x: auto;
}

.field-table,
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-variant-numeric: tabular-nums;
}

.field-table th,
.field-table td,
.comparison-table th,
.comparison-table td {
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--line-soft);
  vertical-align: top;
}

.field-table thead th,
.comparison-table thead th {
  font-family: var(--ui-family);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  text-align: left;
}

.criteria-label {
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.row-emphasis > * {
  background: rgba(15,124,107,0.06);
}

.col-emphasis {
  background: linear-gradient(180deg, rgba(15,124,107,0.07), rgba(15,124,107,0.02));
}

.best-fit-row > *:first-child {
  color: var(--accent);
  font-weight: 700;
}

.comparison-grid {
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
}

.criteria-rows {
  display: grid;
  gap: var(--space-3);
}

.criteria-rows > * {
  padding: var(--space-4) 0;
  border-top: 1px solid var(--line-soft);
}

.filter-chips {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.filter-chip {
  appearance: none;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--muted);
  border-radius: 999px;
  padding: 0.55rem 0.9rem;
  font-family: var(--ui-family);
  font-size: 0.82rem;
  cursor: pointer;
}

.filter-chip.is-active,
.filter-chip[aria-pressed='true'] {
  color: var(--text);
  border-color: var(--accent);
  background: rgba(15,124,107,0.07);
}

[data-filter-item].is-hidden {
  display: none !important;
}

.decision-strip,
.next-route,
.cta-band {
  padding-block: var(--space-7);
}

.cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4) var(--space-5);
  margin-top: var(--space-5);
}

.text-link-arrow {
  font-family: var(--ui-family);
  font-weight: 600;
  text-decoration: none;
}

.site-footer {
  padding-block: var(--space-7) var(--space-8);
  border-top: 1px solid var(--line);
}

.footer-grid {
  grid-template-columns: 1.2fr 0.8fr;
  align-items: start;
}

.footer-nav {
  display: grid;
  gap: var(--space-2);
}

.footer-nav a {
  text-decoration: none;
  color: var(--muted);
  font-family: var(--ui-family);
}

.footer-nav a:hover,
.footer-nav a:focus-visible {
  color: var(--text);
}

.reveal-on-scroll {
  transform: translateY(0);
}

.is-revealed {
  transform: translateY(0);
}

@media (prefers-reduced-motion: no-preference) {
  .reveal-on-scroll {
    transition: transform 360ms ease, opacity 360ms ease;
  }

  .reveal-on-scroll[data-reveal='pending'] {
    opacity: 0.999;
    transform: translateY(10px);
  }

  .reveal-on-scroll.is-revealed {
    opacity: 1;
    transform: translateY(0);
  }

  .hero-trace::before,
  .route-line::before,
  .nav-link::before {
    transition: transform 300ms ease, opacity 250ms ease;
  }

  .hero-trace.animate-line::before,
  .route-line.animate-line::before {
    transform-origin: left;
    animation: drawLine 420ms ease both;
  }
}

@keyframes drawLine {
  from {
    transform: scaleX(0.25);
    opacity: 0.4;
  }
  to {
    transform: scaleX(1);
    opacity: 1;
  }
}

@media (max-width: 980px) {
  :root {
    --container: min(100vw - 32px, 1280px);
    --header-height: 64px;
    --grid-gap: var(--space-5);
  }

  .topbar {
    grid-template-columns: 1fr auto;
  }

  .header-meta {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    justify-self: end;
  }

  .primary-nav {
    grid-column: 1 / -1;
    justify-self: stretch;
    display: none;
    padding-top: var(--space-3);
  }

  .site-header.nav-open .primary-nav {
    display: block;
  }

  .nav-list {
    flex-direction: column;
    align-items: flex-start;
    border-top: 1px solid var(--line);
    padding-top: var(--space-3);
  }

  .hero-grid,
  .split-layout,
  .rail-layout,
  .comparison-grid,
  .footer-grid,
  .two-up,
  .three-up {
    grid-template-columns: 1fr;
  }

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

  .route-panel {
    grid-column: auto;
  }

  .side-column,
  .sticky-rail,
  .anchor-nav {
    position: static;
  }

  .hero-title {
    max-width: 14ch;
  }
}

@media (max-width: 640px) {
  :root {
    --container: calc(100vw - 24px);
    --anchor-offset: 84px;
  }

  .hero-spread,
  .chapter-band,
  .decision-strip,
  .next-route,
  .cta-band,
  .site-footer {
    padding-block: var(--space-6);
  }

  .chapter-grid,
  .facts-grid {
    grid-template-columns: 1fr;
  }

  .chapter-panel,
  .route-panel,
  .note-panel,
  .comparison-panel,
  .fact-panel,
  .quote-panel,
  .image-panel,
  .callout-strip,
  .metric-block,
  .plan-panel,
  .table-wrap {
    padding: var(--space-4);
  }
}