/*
  Minimal dark theme for InsightLab (2025).
  The stylesheet defines design tokens first, then applies layout primitives
  shared by the narrative column, chart cards, and metadata sidebar.
*/

/*
  Responsive audit notes (2025-03-07):
  - Default two-column layout-grid constrains the main column on phones and can introduce horizontal scroll.
  - Masthead navigation pills wrap unpredictably on narrow widths and crowd the header.
  - Sticky meta-column with fixed width clashes with mobile stacking and eats horizontal space.
  - Chart canvas heights use fixed clamps that feel cramped on desktops and oversized on very small devices.
  - Typography and spacing tokens are static, so headings and gutters do not scale smoothly between breakpoints.
*/

:root {
  color-scheme: dark;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-serif: 'Fraunces', 'Times New Roman', serif;
  --font-mono: 'IBM Plex Mono', 'SFMono-Regular', ui-monospace;

  --bg: #05070d;
  --bg-alt: #090f1c;
  --surface: #10192e;
  --surface-alt: #13223a;
  --text: #f0f4ff;
  --muted: #c0c9dd;
  --soft: #7f8ba4;
  --accent: #7af5ff;
  --accent-soft: rgba(122, 245, 255, 0.16);
  --border: rgba(122, 245, 255, 0.14);
  --border-subtle: rgba(126, 141, 176, 0.22);
  --shadow-soft: 0 28px 60px -40px rgba(4, 8, 20, 0.8);

  --radius-base: 18px;
  --radius-small: 12px;
  --space-2xs: clamp(0.32rem, 0.28rem + 0.35vw, 0.5rem);
  --space-xs: clamp(0.55rem, 0.48rem + 0.6vw, 0.9rem);
  --space-sm: clamp(0.85rem, 0.76rem + 0.7vw, 1.2rem);
  --space-md: clamp(1.3rem, 1.12rem + 1.1vw, 1.9rem);
  --space-lg: clamp(1.8rem, 1.58rem + 1.6vw, 2.6rem);
  --space-xl: clamp(2.4rem, 2.1rem + 2.4vw, 3.4rem);
  --max-content-width: clamp(32rem, 85vw, 46rem);
  --max-layout-width: min(1080px, 94vw);

  --transition-base: 220ms ease;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: clamp(1rem, 0.96rem + 0.28vw, 1.12rem);
  line-height: 1.75;
  letter-spacing: 0.01em;
  background: var(--bg);
  color: var(--muted);
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(circle at 12% 18%, rgba(122, 245, 255, 0.1), transparent 55%),
    radial-gradient(circle at 78% 12%, rgba(148, 103, 255, 0.08), transparent 62%),
    radial-gradient(circle at 50% 85%, rgba(122, 245, 255, 0.05), transparent 70%);
  pointer-events: none;
  z-index: -1;
}

main,
section,
header,
footer {
  display: block;
}

img,
canvas,
svg,
video {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--muted);
  text-decoration: underline;
  text-decoration-color: rgba(122, 245, 255, 0.3);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
  transition: color var(--transition-base), text-decoration-color var(--transition-base),
    text-shadow var(--transition-base);
}

a:hover,
a:focus-visible {
  color: var(--accent);
  text-decoration-color: var(--accent);
  text-shadow: 0 0 8px rgba(122, 245, 255, 0.35);
  outline: 2px solid transparent;
  outline-offset: 2px;
  box-shadow: 0 0 0 3px rgba(122, 245, 255, 0.12);
}

strong,
b {
  color: var(--text);
}

h1,
h2,
h3,
h4,
h5,
h6 {
  color: var(--text);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
  color: var(--bg);
  background: var(--accent);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-small);
  font-weight: 600;
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
  width: auto;
  height: auto;
  z-index: 1000;
}

.site-frame {
  width: min(100%, var(--max-layout-width));
  margin-inline: auto;
  padding: clamp(1.4rem, 1.1rem + 2.5vw, 2.6rem) clamp(1rem, 0.8rem + 3vw, 2.5rem) var(--space-xl);
  display: grid;
  gap: var(--space-xl);
}

.masthead {
  background: var(--bg-alt);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-base);
  padding: var(--space-lg);
  box-shadow: 0 32px 80px -60px rgba(6, 14, 30, 0.85);
}

.masthead__title-group {
  display: grid;
  gap: var(--space-xs);
  max-width: var(--max-content-width);
}

.masthead__title,
.section__header h2,
.meta-card h2 {
  text-wrap: balance;
}

.masthead__kicker {
  text-transform: uppercase;
  letter-spacing: 0.32em;
  font-size: 0.72rem;
  color: rgba(122, 245, 255, 0.72);
}

.masthead__title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(2.2rem, 1.7rem + 2.5vw, 3.2rem);
  color: var(--text);
  letter-spacing: -0.01em;
}

.masthead__title-note {
  font-size: 0.9em;
  color: var(--soft);
}

.masthead__byline {
  color: var(--soft);
  font-weight: 500;
}

.masthead__lead {
  color: var(--muted);
  margin-top: var(--space-xs);
}

.masthead__nav {
  margin-top: var(--space-md);
  border-top: 1px solid var(--border-subtle);
  padding-top: var(--space-sm);
}

.masthead__nav ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--space-2xs);
  padding: 0;
  margin: 0;
  list-style: none;
}

.masthead__nav a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  justify-content: center;
  padding: 0.4rem 0.8rem;
  background: rgba(122, 245, 255, 0.05);
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 0.9rem;
  color: var(--muted);
  width: 100%;
}

.masthead__nav a:hover,
.masthead__nav a:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 0 0 6px rgba(122, 245, 255, 0.08);
}

.masthead__stats {
  margin-top: var(--space-lg);
  display: grid;
  gap: var(--space-md);
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  color: var(--muted);
}

.stat-label {
  display: block;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.28em;
  margin-bottom: var(--space-2xs);
  color: rgba(122, 245, 255, 0.6);
}

.stat-value {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  color: var(--text);
}

.layout-grid {
  display: grid;
  gap: var(--space-xl);
  margin-top: var(--space-xl);
}

.content-column {
  display: grid;
  gap: var(--space-xl);
}

.meta-column {
  display: grid;
  gap: var(--space-lg);
  align-content: start;
  position: static;
}

.section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-base);
  padding: var(--space-lg);
  box-shadow: 0 30px 80px -60px rgba(4, 12, 28, 0.9);
}

.section__header {
  display: grid;
  gap: var(--space-xs);
  margin-bottom: var(--space-md);
}

.section__eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.28em;
  font-size: 0.7rem;
  color: rgba(122, 245, 255, 0.72);
}

.section__header h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(1.55rem, 1.35rem + 1.4vw, 2.2rem);
  color: var(--text);
}

.section__intro {
  margin: 0;
  color: var(--muted);
  max-width: var(--max-content-width);
}

.section__body {
  display: grid;
  gap: var(--space-sm);
  max-width: var(--max-content-width);
}

.bullet-list {
  margin: 0;
  padding-left: 1.2rem;
  display: grid;
  gap: var(--space-2xs);
}

.bullet-list li {
  margin: 0;
}

.bullet-list li::marker {
  color: var(--accent);
}

.code-block {
  background: var(--surface-alt);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-base);
  padding: clamp(1.1rem, 0.9rem + 1vw, var(--space-md));
  display: grid;
  gap: var(--space-sm);
}

.code-block h3 {
  margin: 0;
  font-size: 1rem;
  color: var(--accent);
}

pre {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--text);
  overflow-x: auto;
}

code {
  font-family: var(--font-mono);
  font-size: 0.95em;
  color: var(--accent);
  background: rgba(122, 245, 255, 0.08);
  padding: 0.15em 0.4em;
  border-radius: 0.4rem;
  border: 1px solid rgba(122, 245, 255, 0.2);
}

pre code {
  background: transparent;
  border: 0;
  color: var(--text);
  padding: 0;
}

.table-card {
  background: var(--surface-alt);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-base);
  padding: var(--space-md);
  display: grid;
  gap: var(--space-sm);
  overflow-x: auto;
}

.table-card h3 {
  margin: 0;
  font-size: 1rem;
  color: var(--accent);
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 460px;
}

th,
td {
  padding: 0.7rem 0.9rem;
  text-align: left;
  border-bottom: 1px solid var(--border-subtle);
}

th {
  font-size: 0.85rem;
  color: var(--accent);
  letter-spacing: 0.02em;
}

tbody tr:nth-child(even) {
  background: rgba(122, 245, 255, 0.03);
}

tbody tr:hover {
  background: rgba(122, 245, 255, 0.05);
  color: var(--text);
}

tr:last-child td {
  border-bottom: none;
}

.chart-grid {
  display: grid;
  gap: var(--space-lg);
}

.chart-card {
  background: var(--surface-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-base);
  padding: var(--space-lg);
  display: grid;
  gap: var(--space-sm);
  box-shadow: 0 32px 90px -64px rgba(6, 16, 36, 0.92);
}

.chart-card__header {
  display: grid;
  gap: var(--space-2xs);
}

.chart-card__eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.28em;
  font-size: 0.68rem;
  color: rgba(122, 245, 255, 0.72);
}

.chart-card__header h3 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(1.3rem, 1.15rem + 0.9vw, 1.7rem);
  color: var(--text);
}

.chart-card__summary {
  margin: 0;
  color: var(--muted);
}

.chart-card__note {
  margin: 0;
  font-size: 0.95rem;
  color: var(--muted);
}

.chart-card__canvas {
  position: relative;
  min-height: clamp(220px, 55vw, 360px);
}

.chart-card__canvas canvas {
  width: 100% !important;
  height: 100% !important;
}

.chart-card__controls {
  display: inline-flex;
  flex-wrap: wrap;
  gap: var(--space-2xs);
  background: rgba(122, 245, 255, 0.06);
  padding: var(--space-2xs);
  border-radius: 999px;
  border: 1px solid rgba(122, 245, 255, 0.12);
}

.chart-tab {
  border: none;
  background: transparent;
  color: var(--muted);
  font: inherit;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  transition: background var(--transition-base), color var(--transition-base),
    box-shadow var(--transition-base);
}

.chart-tab.is-active {
  background: var(--accent-soft);
  color: var(--accent);
  box-shadow: 0 0 0 4px rgba(122, 245, 255, 0.12);
}

.chart-tab:hover,
.chart-tab:focus-visible {
  background: var(--accent-soft);
  color: var(--accent);
}

.chart-tab:focus-visible {
  outline: 2px solid transparent;
  outline-offset: 2px;
  box-shadow: 0 0 0 4px rgba(122, 245, 255, 0.18);
}

.chart-card__meta {
  display: grid;
  gap: var(--space-sm);
  margin: 0;
}

.chart-card__meta dt {
  font-size: 0.8rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: rgba(122, 245, 255, 0.72);
}

.chart-card__meta dd {
  margin: 0;
  color: var(--muted);
}

.chart-card__fallback {
  margin: 0;
  padding: 0.75rem;
  border-radius: var(--radius-small);
  background: rgba(122, 245, 255, 0.08);
  color: var(--accent);
  border: 1px solid rgba(122, 245, 255, 0.3);
}

.meta-card {
  background: var(--surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-base);
  padding: var(--space-md);
  display: grid;
  gap: var(--space-sm);
  box-shadow: 0 24px 70px -60px rgba(6, 14, 32, 0.85);
}

.meta-card h2 {
  margin: 0;
  font-size: clamp(1.2rem, 1.08rem + 0.8vw, 1.6rem);
  color: var(--text);
}

.meta-card__lead {
  margin: 0;
  color: var(--muted);
}

.meta-card__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: var(--space-2xs);
}

.meta-card__list li,
.meta-card__list dd {
  margin: 0;
}

.meta-card__list dt {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.24em;
  color: rgba(122, 245, 255, 0.72);
  margin-bottom: var(--space-2xs);
}

.meta-card__list dd {
  color: var(--muted);
}

.grid-two {
  display: grid;
  gap: var(--space-md);
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.site-footer {
  margin-top: 0;
  text-align: center;
  color: var(--soft);
  display: grid;
  gap: var(--space-2xs);
}

.site-footer__link {
  justify-self: center;
  color: var(--accent);
  font-weight: 600;
}

.site-footer__link:hover,
.site-footer__link:focus-visible {
  text-shadow: 0 0 10px rgba(122, 245, 255, 0.35);
}

.js-reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 440ms ease, transform 440ms ease;
}

.js-reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (min-width: 640px) {
  :root {
    --max-layout-width: min(1120px, 92vw);
  }

  .masthead__nav ul {
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  }

  .masthead__stats {
    gap: var(--space-sm);
  }
}

@media (min-width: 768px) {
  .site-frame {
    padding-inline: clamp(1.5rem, 1rem + 2vw, 3rem);
  }

  .masthead {
    padding: var(--space-lg);
  }

  .masthead__nav ul {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-start;
    gap: var(--space-2xs);
  }

  .masthead__nav a {
    width: auto;
  }

  .chart-card__canvas {
    min-height: clamp(260px, 38vw, 420px);
  }
}

@media (min-width: 1024px) {
  .layout-grid {
    grid-template-columns: minmax(0, 1fr) minmax(260px, 320px);
    align-items: start;
  }

  .meta-column {
    position: sticky;
    top: 1.5rem;
    height: fit-content;
  }

  .masthead__nav ul {
    gap: var(--space-sm);
  }
}

@media (min-width: 1280px) {
  :root {
    --max-layout-width: min(1180px, 88vw);
  }

  .layout-grid {
    column-gap: clamp(2.5rem, 2rem + 1.5vw, 3.5rem);
  }

  .chart-card__canvas {
    min-height: clamp(300px, 28vw, 460px);
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .js-reveal {
    opacity: 1;
    transform: none;
  }
}