:root {
  --bg: #fbf6ec;
  --bg-strong: #f2e4cb;
  --ink: #1b1a18;
  --muted: #625a4d;
  --accent: #be4f23;
  --accent-soft: rgba(190, 79, 35, 0.12);
  --teal: #0f6b62;
  --gold: #d68e1c;
  --border: rgba(27, 26, 24, 0.12);
  --shadow: 0 24px 70px rgba(47, 36, 20, 0.12);
  --radius: 24px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    radial-gradient(circle at top left, rgba(214, 142, 28, 0.18), transparent 30%),
    radial-gradient(circle at 80% 15%, rgba(15, 107, 98, 0.14), transparent 24%),
    linear-gradient(180deg, #fffaf0 0%, var(--bg) 55%, #f7f0e1 100%);
  color: var(--ink);
  font-family: "Avenir Next", "Helvetica Neue", "Segoe UI", sans-serif;
  line-height: 1.55;
}

code,
pre {
  font-family: "SFMono-Regular", "Menlo", "Monaco", "Consolas", "Liberation Mono", monospace;
}

code:not(pre code) {
  padding: 0.12rem 0.38rem;
  border-radius: 0.42rem;
  background: rgba(27, 26, 24, 0.08);
  color: var(--ink);
  font-size: 0.92em;
}

.page-shell {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(27, 26, 24, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(27, 26, 24, 0.02) 1px, transparent 1px);
  background-size: 30px 30px;
  pointer-events: none;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.4), transparent 85%);
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  padding: 18px 6vw;
  background: rgba(251, 246, 236, 0.82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(27, 26, 24, 0.08);
}

.brand,
.nav a,
.footer a,
.resource-card {
  color: inherit;
  text-decoration: none;
}

.brand {
  font-family: "Iowan Old Style", "Palatino Linotype", serif;
  font-size: 1.15rem;
  font-weight: 700;
}

.nav {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
}

.nav a {
  color: var(--muted);
  font-size: 0.94rem;
}

main {
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
}

.hero,
.section,
.footer {
  position: relative;
  z-index: 1;
}

.hero {
  display: grid;
  grid-template-columns: 1.4fr 0.9fr;
  gap: 28px;
  padding: 72px 0 48px;
}

.eyebrow,
.panel-kicker,
.fact-label {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.76rem;
  color: var(--accent);
}

h1,
h2,
h3 {
  font-family: "Iowan Old Style", "Palatino Linotype", serif;
  line-height: 1.05;
  margin: 0 0 14px;
}

h1 {
  font-size: clamp(2.8rem, 6vw, 5.4rem);
  max-width: 12ch;
}

h2 {
  font-size: clamp(2rem, 4vw, 3.2rem);
}

h3 {
  font-size: 1.28rem;
}

.lead,
.section-head p,
.signal-card p,
.loop-callout p,
.lesson-card p,
.insight-card p,
.stage-card p,
.math-card p,
.resource-card p,
.command-card pre,
.comparison-row:not(.comparison-header) span:last-child,
.experiment-row:not(.experiment-header) span:last-child {
  color: var(--muted);
}

.cta-row {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin: 28px 0 30px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 18px;
  border-radius: 999px;
  font-weight: 700;
  border: 1px solid var(--border);
  text-decoration: none;
}

.button.primary {
  background: var(--ink);
  color: #fff7ea;
}

.button.secondary {
  background: rgba(255, 255, 255, 0.74);
  color: var(--ink);
}

.hero-facts,
.insight-grid,
.resource-grid,
.command-grid,
.lesson-grid,
.pipeline-grid {
  display: grid;
  gap: 18px;
}

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

.fact-card,
.panel-card,
.signal-card,
.stage-card,
.insight-card,
.lesson-card,
.diagram-card,
.math-card,
.command-card,
.resource-card,
.loop-callout {
  background: rgba(255, 253, 247, 0.78);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.fact-card,
.panel-card,
.signal-card,
.stage-card,
.insight-card,
.lesson-card,
.diagram-card,
.math-card,
.loop-callout {
  padding: 22px;
}

.hero-panel {
  display: grid;
  gap: 18px;
  align-content: start;
}

.metric-list {
  list-style: none;
  padding: 0;
  margin: 14px 0 0;
}

.metric-list li,
.comparison-row,
.experiment-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
  align-items: center;
  padding: 12px 0;
}

.metric-list li + li {
  border-top: 1px solid rgba(27, 26, 24, 0.08);
}

.signal-card {
  background: linear-gradient(140deg, rgba(15, 107, 98, 0.12), rgba(214, 142, 28, 0.14));
}

.signal-title {
  margin: 0 0 10px;
  font-weight: 700;
}

.section {
  padding: 56px 0;
}

.section-head {
  max-width: 760px;
  margin-bottom: 28px;
}

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

.stage-number {
  display: inline-block;
  margin-bottom: 16px;
  color: var(--teal);
  font-weight: 800;
  letter-spacing: 0.08em;
}

.loop-layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 22px;
  margin-bottom: 22px;
}

.loop-steps {
  margin: 0;
  padding-left: 22px;
  display: grid;
  gap: 14px;
}

.loop-steps li {
  padding: 16px 18px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--border);
  border-radius: 18px;
}

.loop-steps span {
  display: block;
  color: var(--muted);
  margin-top: 4px;
}

.diagram-card {
  overflow: auto;
}

.mermaid {
  min-width: 680px;
}

.mermaid svg {
  max-width: 100%;
  height: auto;
}

.comparison-table,
.experiment-table {
  display: grid;
  margin-bottom: 24px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.comparison-row,
.experiment-row {
  background: rgba(255, 255, 255, 0.78);
  padding: 18px 20px;
  border-bottom: 1px solid rgba(27, 26, 24, 0.08);
}

.comparison-row {
  grid-template-columns: 1.1fr 0.8fr 0.8fr 0.55fr 0.55fr 0.55fr 1.2fr;
}

.experiment-row {
  grid-template-columns: 1.2fr 0.7fr 0.5fr 0.6fr 0.6fr 1.4fr;
}

.comparison-header,
.experiment-header {
  background: var(--ink);
  color: #fff7ea;
  font-weight: 700;
}

.best-row {
  background: linear-gradient(135deg, rgba(15, 107, 98, 0.13), rgba(214, 142, 28, 0.12));
}

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

.lesson-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.math-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-bottom: 18px;
}

.equation-block {
  margin: 14px 0;
  padding: 14px 16px;
  overflow: auto;
  border-radius: 18px;
  border: 1px solid rgba(27, 26, 24, 0.08);
  background: rgba(27, 26, 24, 0.95);
  color: #f6efdf;
  font-size: 0.92rem;
}

.equation-block code,
.command-card pre code {
  display: block;
  white-space: pre-wrap;
  word-break: break-word;
  line-height: 1.6;
}

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

.command-card {
  padding: 0;
  overflow: hidden;
}

.command-card h3 {
  padding: 20px 22px 0;
}

.command-card pre {
  margin: 0;
  padding: 18px 22px 22px;
  overflow: auto;
  font-size: 0.88rem;
  background: rgba(27, 26, 24, 0.96);
  color: #f6efdf;
}

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

.resource-card {
  padding: 22px;
  transition: transform 180ms ease, border-color 180ms ease;
}

.resource-card:hover {
  transform: translateY(-4px);
  border-color: rgba(190, 79, 35, 0.35);
}

.footer {
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
  padding: 28px 0 56px;
  color: var(--muted);
}

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 500ms ease, transform 500ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1040px) {
  .hero,
  .loop-layout {
    grid-template-columns: 1fr;
  }

  .pipeline-grid,
  .math-grid,
  .lesson-grid,
  .command-grid,
  .resource-grid,
  .insight-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .comparison-row {
    grid-template-columns: 1.1fr 0.8fr 0.8fr 0.6fr 0.6fr 0.6fr 1fr;
  }

  .experiment-row {
    grid-template-columns: 1.1fr 0.7fr 0.5fr 0.6fr 0.6fr 1fr;
  }
}

@media (max-width: 720px) {
  body {
    font-size: 15px;
  }

  .topbar,
  main,
  .footer {
    width: min(100% - 24px, 100%);
    padding-left: 0;
    padding-right: 0;
  }

  .topbar {
    display: block;
  }

  .nav {
    margin-top: 12px;
    gap: 12px;
  }

  .hero {
    padding-top: 42px;
  }

  .hero-facts,
  .pipeline-grid,
  .math-grid,
  .lesson-grid,
  .command-grid,
  .resource-grid,
  .insight-grid {
    grid-template-columns: 1fr;
  }

  .comparison-table,
  .experiment-table {
    gap: 12px;
    border: 0;
    box-shadow: none;
    background: none;
  }

  .comparison-row,
  .experiment-row,
  .comparison-header,
  .experiment-header {
    grid-template-columns: 1fr;
    gap: 6px;
    border-radius: 18px;
    border: 1px solid var(--border);
    margin-bottom: 10px;
  }

  .comparison-header,
  .experiment-header {
    display: none;
  }

  .mermaid {
    min-width: 0;
  }
}