/* ============================================================
   Behavior-Inheritance Simulator
   Palette: deep indigo (genes) + warm amber (environment)
   ============================================================ */

:root {
  /* Type scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Radii */
  --radius-sm: 0.375rem;
  --radius-md: 0.625rem;
  --radius-lg: 1rem;
  --radius-full: 9999px;

  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Fonts */
  --font-display: 'Fraunces', Georgia, serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;

  /* Content widths */
  --content-wide: 1240px;
}

/* Light theme — cream + deep indigo + warm amber */
:root,
[data-theme='light'] {
  --color-bg: #f6f2ea;
  --color-surface: #fbf7ef;
  --color-surface-2: #ffffff;
  --color-surface-offset: #efe9dc;
  --color-surface-dynamic: #e6dfce;
  --color-border: #d9d0bb;
  --color-divider: #e5dcc7;

  --color-text: #1c1830;
  --color-text-muted: #6b6480;
  --color-text-faint: #a29ab0;
  --color-text-inverse: #fbf7ef;

  --color-primary: #3b2f7c; /* deep indigo — "genes" */
  --color-primary-hover: #2c2360;
  --color-primary-tint: #ded9f0;

  --color-accent: #c9761c; /* warm amber — "environment" */
  --color-accent-hover: #a15d10;
  --color-accent-tint: #f2ddbf;

  --color-third: #7b6a3f; /* olive — "non-shared" */
  --color-third-tint: #e5decf;

  --shadow-sm: 0 1px 2px rgba(28, 24, 48, 0.06);
  --shadow-md: 0 6px 20px rgba(28, 24, 48, 0.08);
  --shadow-lg: 0 20px 48px rgba(28, 24, 48, 0.12);
}

[data-theme='dark'] {
  --color-bg: #131120;
  --color-surface: #1a1830;
  --color-surface-2: #211f3a;
  --color-surface-offset: #1e1c34;
  --color-surface-dynamic: #2a2745;
  --color-border: #363258;
  --color-divider: #2a2745;

  --color-text: #eae5f5;
  --color-text-muted: #8f8aa8;
  --color-text-faint: #5a5674;
  --color-text-inverse: #1a1830;

  --color-primary: #9e91ff;
  --color-primary-hover: #b6acff;
  --color-primary-tint: #2c2856;

  --color-accent: #e9a24c;
  --color-accent-hover: #f4b567;
  --color-accent-tint: #4a361a;

  --color-third: #c8b378;
  --color-third-tint: #3a331d;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 6px 20px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 20px 48px rgba(0, 0, 0, 0.5);
}

/* ---------- Base ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: var(--space-16);
}
body {
  min-height: 100dvh;
  line-height: 1.6;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background: var(--color-bg);
  background-image:
    radial-gradient(
      circle at 15% 10%,
      color-mix(in oklab, var(--color-primary) 8%, transparent) 0%,
      transparent 40%
    ),
    radial-gradient(
      circle at 88% 5%,
      color-mix(in oklab, var(--color-accent) 8%, transparent) 0%,
      transparent 45%
    );
  background-attachment: fixed;
}
img,
svg,
canvas {
  display: block;
  max-width: 100%;
}
button {
  cursor: pointer;
  background: none;
  border: none;
  font: inherit;
  color: inherit;
}
input {
  font: inherit;
  color: inherit;
}
h1,
h2,
h3,
h4 {
  text-wrap: balance;
  line-height: 1.15;
  font-family: var(--font-display);
  font-weight: 500;
  letter-spacing: -0.01em;
}
p {
  text-wrap: pretty;
}
a {
  color: var(--color-primary);
  text-decoration: none;
  border-bottom: 1px solid color-mix(in oklab, var(--color-primary) 30%, transparent);
  transition: border-color var(--transition-interactive);
}
a:hover {
  border-bottom-color: var(--color-primary);
}
code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  padding: 0.1em 0.35em;
  background: var(--color-surface-offset);
  border-radius: var(--radius-sm);
  color: var(--color-primary);
}
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* ---------- Header ---------- */
.site-header {
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: var(--space-6) var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}
.brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.brand-mark {
  width: 36px;
  height: 36px;
  color: var(--color-primary);
}
.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}
.brand-name {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
}
.brand-sub {
  font-size: 0.78rem;
  color: var(--color-text-muted);
}
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}
.header-link {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  border: none;
}
.header-link:hover {
  color: var(--color-text);
}
.theme-toggle {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border);
  display: inline-grid;
  place-items: center;
  color: var(--color-text-muted);
  background: var(--color-surface);
}
.theme-toggle:hover {
  color: var(--color-text);
  border-color: var(--color-primary);
}

/* ---------- Hero ---------- */
main {
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: 0 var(--space-6) var(--space-24);
}
.hero {
  padding: var(--space-10) 0 var(--space-12);
  max-width: 900px;
}
.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}
.hero-title {
  font-size: var(--text-2xl);
  font-weight: 400;
  margin-bottom: var(--space-5);
  font-family: var(--font-display);
}
.hero-accent {
  color: var(--color-accent);
  font-style: italic;
}
.hero-lede {
  color: var(--color-text-muted);
  font-size: var(--text-base);
  max-width: 68ch;
}
.hero-lede em {
  color: var(--color-text);
  font-style: italic;
}

/* ---------- Workbench layout ---------- */
.workbench {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: var(--space-6);
  align-items: start;
}
@media (max-width: 1000px) {
  .workbench {
    grid-template-columns: 1fr;
  }
}

/* ---------- Panels ---------- */
.panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
}
.panel-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-5);
}
.panel-head h2 {
  font-size: 1.1rem;
  font-weight: 500;
}
.panel-sub {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-top: 2px;
}

/* ---------- Controls ---------- */
.controls-panel {
  position: sticky;
  top: var(--space-6);
}
@media (max-width: 1000px) {
  .controls-panel {
    position: static;
  }
}

.control-group {
  margin-bottom: var(--space-5);
}
.control-group + .control-group {
  padding-top: 0;
}
.control-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: var(--space-2);
}
.control-label {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-text);
}
.control-value {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--color-primary);
  background: var(--color-primary-tint);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  font-weight: 500;
}
.control-help {
  font-size: 0.78rem;
  color: var(--color-text-muted);
  margin-top: var(--space-2);
  line-height: 1.5;
}

.divider {
  border: none;
  height: 1px;
  background: var(--color-divider);
  margin: var(--space-6) 0;
}

/* Range sliders */
input[type='range'] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  background: var(--color-surface-offset);
  border-radius: var(--radius-full);
  outline: none;
}
input[type='range']::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--color-primary);
  border: 3px solid var(--color-surface-2);
  box-shadow: var(--shadow-sm);
  cursor: grab;
  transition: transform var(--transition-interactive);
}
input[type='range']::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}
input[type='range']::-webkit-slider-thumb:active {
  cursor: grabbing;
}
input[type='range']::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--color-primary);
  border: 3px solid var(--color-surface-2);
  box-shadow: var(--shadow-sm);
  cursor: grab;
}
input[type='range']:disabled::-webkit-slider-thumb {
  background: var(--color-text-muted);
  cursor: not-allowed;
}
input[type='range']:disabled {
  opacity: 0.7;
}

/* Segmented control */
.segmented {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  padding: 4px;
  gap: 4px;
  background: var(--color-surface-offset);
  border-radius: var(--radius-md);
}
.seg-btn {
  padding: var(--space-2) var(--space-3);
  border-radius: calc(var(--radius-md) - 2px);
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: all var(--transition-interactive);
}
.seg-btn:hover {
  color: var(--color-text);
}
.seg-btn.is-active {
  background: var(--color-surface-2);
  color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

/* Buttons */
.primary-btn {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  border-radius: var(--radius-md);
  font-weight: 500;
  font-size: 0.9rem;
  transition:
    background var(--transition-interactive),
    transform var(--transition-interactive);
  margin-top: var(--space-3);
}
.primary-btn:hover {
  background: var(--color-primary-hover);
}
.primary-btn:active {
  transform: translateY(1px);
}
.ghost-btn {
  font-size: 0.78rem;
  color: var(--color-text-muted);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}
.ghost-btn:hover {
  color: var(--color-text);
  border-color: var(--color-primary);
}

/* ---------- Results ---------- */
.results {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  min-width: 0;
}

.stat-strip {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4);
}
@media (max-width: 720px) {
  .stat-strip {
    grid-template-columns: 1fr;
  }
}
.stat {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}
.stat-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: var(--space-3);
}
.stat-body {
  font-size: 0.88rem;
  color: var(--color-text);
  line-height: 1.55;
}

/* ACE bar */
.ace-bar {
  display: flex;
  width: 100%;
  height: 14px;
  border-radius: var(--radius-full);
  overflow: hidden;
  background: var(--color-surface-offset);
  margin-bottom: var(--space-3);
}
.ace-seg {
  height: 100%;
  transition: width 400ms cubic-bezier(0.16, 1, 0.3, 1);
}
.ace-a {
  background: var(--color-primary);
}
.ace-c {
  background: var(--color-accent);
}
.ace-e {
  background: var(--color-third);
}
.ace-legend {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3) var(--space-4);
  font-size: 0.78rem;
  color: var(--color-text-muted);
}
.ace-legend b {
  color: var(--color-text);
  font-weight: 500;
  font-family: var(--font-mono);
  margin-left: 4px;
}
.dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-right: 6px;
  vertical-align: 1px;
}
.dot-a {
  background: var(--color-primary);
}
.dot-c {
  background: var(--color-accent);
}
.dot-e {
  background: var(--color-third);
}

/* Chart panels */
.legend-inline {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  font-size: 0.75rem;
  color: var(--color-text-muted);
}
.swatch {
  display: inline-block;
  width: 12px;
  height: 3px;
  border-radius: 2px;
  margin-right: 6px;
  vertical-align: 3px;
}
.swatch-pop {
  background: var(--color-text-muted);
}
.swatch-high {
  background: var(--color-primary);
}
.swatch-low {
  background: var(--color-accent);
}

.chart-wrap {
  position: relative;
  height: 320px;
  width: 100%;
}
.chart-wrap-scatter {
  height: 280px;
}

/* ---------- Concepts ---------- */
.section-head {
  max-width: 720px;
  margin-bottom: var(--space-8);
}
.section-lede {
  color: var(--color-text-muted);
}
.concepts,
.methodology {
  padding-top: var(--space-20);
}
.concept-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-4);
}
.concept-card {
  padding: var(--space-6);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  transition:
    transform var(--transition-interactive),
    border-color var(--transition-interactive);
}
.concept-card:hover {
  transform: translateY(-2px);
  border-color: var(--color-primary);
}
.concept-card-accent {
  border-color: var(--color-accent);
  background: color-mix(in oklab, var(--color-accent) 5%, var(--color-surface));
}
.concept-card-accent:hover {
  border-color: var(--color-accent);
}
.concept-tag {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-primary);
  background: var(--color-primary-tint);
  padding: 3px 8px;
  border-radius: var(--radius-sm);
}
.concept-card-accent .concept-tag {
  color: var(--color-accent);
  background: var(--color-accent-tint);
}
.concept-card h3 {
  font-size: 1.05rem;
  font-weight: 500;
  font-family: var(--font-display);
}
.concept-card p {
  font-size: 0.88rem;
  color: var(--color-text-muted);
}
.concept-card em {
  color: var(--color-text);
  font-style: italic;
}

/* ---------- Methodology ---------- */
.method-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-5);
  margin-bottom: var(--space-6);
}
.method-block {
  padding: var(--space-5);
  border-left: 2px solid var(--color-primary);
}
.method-block h3 {
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-primary);
  margin-bottom: var(--space-2);
}
.method-block p {
  font-size: 0.9rem;
  color: var(--color-text-muted);
}
.method-block code {
  font-size: 0.82rem;
}
.caveat {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  padding: var(--space-5);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  max-width: 900px;
}

/* ---------- Footer ---------- */
.site-footer {
  margin-top: var(--space-20);
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-divider);
  font-size: 0.82rem;
  color: var(--color-text-muted);
}

/* ---------- Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}