:root {
  --bg: #f5f4f1;
  --surface: rgba(255, 255, 255, 0.8);
  --surface-strong: #ffffff;
  --border: rgba(38, 42, 56, 0.08);
  --text: #181a1f;
  --muted: #5d6272;
  --accent: #2f5bff;
  --accent-soft: rgba(47, 91, 255, 0.1);
  --warn: #e46e37;
  --warn-soft: rgba(228, 110, 55, 0.12);
  --good: #3f8554;
  --good-soft: rgba(63, 133, 84, 0.12);
  --shadow: 0 20px 40px rgba(26, 31, 46, 0.06);
  --radius-lg: 28px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --content-width: 1120px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Inter", "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(47, 91, 255, 0.08), transparent 30%),
    radial-gradient(circle at left 20%, rgba(228, 110, 55, 0.08), transparent 28%),
    var(--bg);
}

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

code {
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.92em;
}

.page-shell {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 32px;
  max-width: 1480px;
  margin: 0 auto;
  padding: 24px;
}

.rail {
  position: sticky;
  top: 24px;
  align-self: start;
  height: calc(100vh - 48px);
}

.rail__inner {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  height: 100%;
  padding: 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(16px);
  box-shadow: var(--shadow);
}

.rail__title,
.hero__headline,
.section__header h2,
.footer h2,
.insight-card h3,
.method-card h3 {
  font-family: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Georgia, serif;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.rail__title {
  font-size: 2rem;
  line-height: 1;
  margin: 0.2rem 0 0.7rem;
}

.rail__subtitle {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.rail__nav {
  display: grid;
  gap: 10px;
  margin-top: 28px;
}

.rail__nav a {
  padding: 10px 12px;
  border-radius: 999px;
  color: var(--muted);
  transition: 180ms ease;
}

.rail__nav a:hover,
.rail__nav a.is-active {
  color: var(--text);
  background: var(--surface-strong);
}

.story {
  max-width: var(--content-width);
}

.section,
.footer {
  margin-bottom: 28px;
  padding: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  backdrop-filter: blur(16px);
  box-shadow: var(--shadow);
}

.hero {
  padding: 18px;
  background: transparent;
  border: none;
  box-shadow: none;
}

.hero__card {
  padding: 44px;
  border-radius: 36px;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.92), rgba(255, 255, 255, 0.78)),
    linear-gradient(135deg, rgba(47, 91, 255, 0.08), rgba(228, 110, 55, 0.04));
  border: 1px solid rgba(38, 42, 56, 0.08);
  box-shadow: var(--shadow);
}

.eyebrow {
  margin: 0 0 14px;
  text-transform: uppercase;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--muted);
  font-weight: 600;
}

.hero__headline {
  margin: 0;
  font-size: clamp(2.5rem, 4vw, 4.7rem);
  line-height: 0.98;
  max-width: 14ch;
}

.hero__summary,
.section__header p,
.footer p {
  color: var(--muted);
  line-height: 1.7;
  max-width: 72ch;
}

.hero__summary {
  margin-top: 20px;
  font-size: 1.04rem;
}

.hero__stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 32px;
}

.headline-stat,
.metric-card,
.callout,
.method-card,
.insight-card,
.chart-card,
.toggle-card,
.priority-table-card {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
}

.headline-stat {
  padding: 18px;
}

.headline-stat__label,
.metric-card__label,
.callout__label,
.insight-card__label {
  margin: 0 0 10px;
  color: var(--muted);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.headline-stat__value,
.metric-card__value {
  margin: 0;
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
}

.headline-stat__note,
.metric-card__note {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.55;
}

.section__header h2,
.footer h2 {
  margin: 0 0 8px;
  font-size: clamp(2rem, 2.8vw, 3rem);
  line-height: 1.04;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 28px;
}

.metric-card {
  padding: 18px;
}

.chart-grid {
  display: grid;
  gap: 18px;
  margin-top: 22px;
}

.chart-grid--two {
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
}

.toggle-card__subtitle {
  margin: 6px 0 0;
  color: var(--muted);
  line-height: 1.6;
  max-width: 60ch;
}

.footer__close {
  margin-top: 18px;
  max-width: 60ch;
  font-size: 1rem;
}

.chart-grid--wide-left {
  grid-template-columns: minmax(0, 1.5fr) minmax(280px, 0.7fr);
}

.chart-card,
.toggle-card,
.priority-table-card {
  padding: 22px;
}

.chart-card__header,
.toggle-card__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 16px;
}

.chart-card__header h3,
.toggle-card__header h3 {
  margin: 0 0 6px;
  font-size: 1.1rem;
}

.chart-card__header p,
.toggle-card__header p {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

canvas {
  width: 100% !important;
  height: 320px !important;
}

.insight-card {
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.insight-list,
.method-list {
  margin: 16px 0 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.75;
}

.callout-stack {
  display: grid;
  gap: 16px;
}

.callout {
  padding: 18px;
}

.insight-banner {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 20px;
  margin-top: 18px;
  padding: 22px 24px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--surface-strong), rgba(47, 91, 255, 0.05));
  border: 1px solid var(--border);
}

.insight-banner h3 {
  margin: 0;
  font-family: "Iowan Old Style", "Palatino Linotype", Georgia, serif;
  font-size: 1.7rem;
  line-height: 1.1;
}

.insight-banner p:last-child {
  margin: 0;
  color: var(--muted);
  line-height: 1.65;
}

.toggle-group {
  display: inline-flex;
  gap: 8px;
  padding: 6px;
  border-radius: 999px;
  background: var(--bg);
}

.toggle-group__button {
  appearance: none;
  border: none;
  background: transparent;
  color: var(--muted);
  padding: 10px 14px;
  border-radius: 999px;
  font: inherit;
  cursor: pointer;
  transition: 180ms ease;
}

.toggle-group__button.is-active {
  background: var(--surface-strong);
  color: var(--text);
  box-shadow: 0 8px 18px rgba(26, 31, 46, 0.07);
}

.priority-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 24px;
}

.priority-card {
  padding: 20px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--surface-strong);
}

.priority-card__rank {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 999px;
  background: var(--warn-soft);
  color: var(--warn);
  font-weight: 700;
}

.priority-card h3 {
  margin: 14px 0 8px;
  font-size: 1.1rem;
}

.priority-card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.priority-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

.chip {
  padding: 8px 10px;
  border-radius: 999px;
  background: var(--bg);
  color: var(--muted);
  font-size: 0.86rem;
}

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

.priority-table {
  width: 100%;
  border-collapse: collapse;
}

.priority-table th,
.priority-table td {
  padding: 14px 12px;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}

.priority-table th {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.priority-table td {
  font-size: 0.96rem;
  line-height: 1.6;
}

.method-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 24px;
}

.method-card {
  padding: 22px;
}

.schema-stack {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 14px;
}

.schema-pill {
  padding: 10px 14px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 600;
}

.schema-arrow {
  color: var(--muted);
}

.footer {
  text-align: center;
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 600ms ease, transform 600ms ease;
}

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

@media (max-width: 1180px) {
  .page-shell {
    grid-template-columns: 1fr;
  }

  .rail {
    position: static;
    height: auto;
  }

  .rail__inner {
    gap: 18px;
  }

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

@media (max-width: 920px) {
  .hero__stats,
  .metric-grid,
  .priority-grid,
  .method-grid,
  .chart-grid--two,
  .chart-grid--wide-left,
  .insight-banner {
    grid-template-columns: 1fr;
  }

  .section,
  .footer {
    padding: 24px;
  }

  .hero__card {
    padding: 28px;
  }
}

@media (max-width: 680px) {
  .page-shell {
    padding: 14px;
  }

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

  .hero__headline {
    font-size: 2.5rem;
  }

  canvas {
    height: 260px !important;
  }
}