/* ============================================================
   DESIGN TOKENS
   ============================================================ */
:root,
[data-theme='light'] {
  /* Surfaces — cool slate, developer-tool feel */
  --color-bg: #f2f4f5;
  --color-surface: #ffffff;
  --color-surface-2: #f8f9fa;
  --color-surface-offset: #eaedef;
  --color-surface-offset-2: #dfe3e6;
  --color-divider: #dde1e4;
  --color-border: #d3d8db;

  /* Text */
  --color-text: #12171a;
  --color-text-muted: #5b6570;
  --color-text-faint: #97a1a8;
  --color-text-inverse: #f4f6f7;

  /* Primary accent — teal (self-hosted / actions) */
  --color-primary: #0f766e;
  --color-primary-hover: #0b5c56;
  --color-primary-active: #0a4d48;
  --color-primary-highlight: #d8f3ee;

  /* Secondary accent — amber (commercial / warning-adjacent) */
  --color-amber: #b45309;
  --color-amber-highlight: #fbe8d2;

  /* Semantic */
  --color-success: #15803d;
  --color-success-highlight: #dcf5e3;
  --color-error: #b91c1c;
  --color-error-highlight: #fbdede;

  /* Chart series — cool (self-hosted) vs warm (commercial) */
  --chart-libretranslate: #0d9488;
  --chart-lingva: #0891b2;
  --chart-ollama: #65a30d;
  --chart-google: #d97706;
  --chart-deepl: #e11d48;
  --chart-azure: #2563a8;

  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  --transition-interactive: 160ms cubic-bezier(0.16, 1, 0.3, 1);

  --shadow-sm: 0 1px 2px oklch(0.2 0.02 220 / 0.06);
  --shadow-md: 0 4px 14px oklch(0.2 0.02 220 / 0.08);
  --shadow-lg: 0 16px 36px oklch(0.2 0.02 220 / 0.14);

  --content-narrow: 640px;
  --content-default: 980px;
  --content-wide: 1240px;
  --content-full: 100%;

  --font-display: 'Geist', 'Inter', system-ui, sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, monospace;
}

[data-theme='dark'] {
  --color-bg: #0a0e11;
  --color-surface: #10151a;
  --color-surface-2: #141a1f;
  --color-surface-offset: #182028;
  --color-surface-offset-2: #1f2830;
  --color-divider: #212a31;
  --color-border: #2a343c;

  --color-text: #e6ebee;
  --color-text-muted: #8d99a3;
  --color-text-faint: #5c6871;
  --color-text-inverse: #0d1114;

  --color-primary: #2dd4bf;
  --color-primary-hover: #5eead4;
  --color-primary-active: #99f6e4;
  --color-primary-highlight: #123a36;

  --color-amber: #fb923c;
  --color-amber-highlight: #3d2a15;

  --color-success: #4ade80;
  --color-success-highlight: #123a20;
  --color-error: #f87171;
  --color-error-highlight: #3a1717;

  --chart-libretranslate: #2dd4bf;
  --chart-lingva: #38bdf8;
  --chart-ollama: #a3e635;
  --chart-google: #fbbf24;
  --chart-deepl: #fb7185;
  --chart-azure: #60a5fa;

  --shadow-sm: 0 1px 2px oklch(0 0 0 / 0.3);
  --shadow-md: 0 4px 16px oklch(0 0 0 / 0.36);
  --shadow-lg: 0 20px 44px oklch(0 0 0 / 0.5);
}

/* Type scale */
:root {
  --text-xs: clamp(0.75rem, 0.72rem + 0.15vw, 0.8125rem);
  --text-sm: clamp(0.875rem, 0.84rem + 0.2vw, 0.9375rem);
  --text-base: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  --text-lg: clamp(1.125rem, 1.05rem + 0.5vw, 1.375rem);
  --text-xl: clamp(1.375rem, 1.2rem + 1vw, 1.875rem);
  --text-2xl: clamp(1.75rem, 1.4rem + 2vw, 2.5rem);

  --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;
}

/* ============================================================
   GLOBAL / LAYOUT
   ============================================================ */
body {
  overflow-x: hidden;
}

.container {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--space-5);
}
.container--narrow {
  max-width: var(--content-default);
}

.skip-link {
  position: absolute;
  left: -999px;
  top: var(--space-2);
  z-index: 100;
  background: var(--color-primary);
  color: var(--color-text-inverse);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
}
.skip-link:focus {
  left: var(--space-2);
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  font-weight: 650;
  letter-spacing: -0.01em;
}

p {
  max-width: 68ch;
}

.num,
.tabular {
  font-variant-numeric: tabular-nums lining-nums;
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums lining-nums;
}

a {
  color: var(--color-primary);
  text-decoration: none;
}
a:hover {
  color: var(--color-primary-hover);
  text-decoration: underline;
}

section {
  padding-block: clamp(var(--space-12), 6vw, var(--space-20));
  border-bottom: 1px solid var(--color-divider);
}
section:last-of-type {
  border-bottom: none;
}

.section-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}
.section-eyebrow::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  flex-shrink: 0;
}

.section-title {
  font-size: var(--text-xl);
  margin-bottom: var(--space-3);
  max-width: 44ch;
}

.section-desc {
  color: var(--color-text-muted);
  font-size: var(--text-base);
  max-width: 62ch;
  margin-bottom: var(--space-8);
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-end;
  gap: var(--space-6);
}

/* ============================================================
   HEADER
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-3) var(--space-5);
  background: oklch(from var(--color-bg) l c h / 0.88);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-divider);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--text-base);
  color: var(--color-text);
}
.brand:hover {
  color: var(--color-text);
  text-decoration: none;
}
.brand svg {
  color: var(--color-primary);
  width: 26px;
  height: 26px;
  flex-shrink: 0;
}

.main-nav {
  display: none;
  gap: var(--space-6);
}
.main-nav a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  font-weight: 500;
}
.main-nav a:hover {
  color: var(--color-text);
  text-decoration: none;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

@media (min-width: 900px) {
  .main-nav {
    display: flex;
  }
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  background: var(--color-surface);
}
.theme-toggle:hover {
  color: var(--color-text);
  border-color: var(--color-text-faint);
}
.theme-toggle svg {
  width: 18px;
  height: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  font-weight: 600;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  border: 1px solid transparent;
}
.btn-primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}
.btn-primary:hover {
  background: var(--color-primary-hover);
  text-decoration: none;
  color: var(--color-text-inverse);
}
.btn-ghost {
  border-color: var(--color-border);
  color: var(--color-text);
  background: var(--color-surface);
}
.btn-ghost:hover {
  border-color: var(--color-text-faint);
  text-decoration: none;
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  padding-block: clamp(var(--space-12), 8vw, var(--space-24)) clamp(var(--space-10), 6vw, var(--space-16));
}
.hero-grid {
  display: grid;
  gap: var(--space-10);
  align-items: start;
}
@media (min-width: 960px) {
  .hero-grid {
    grid-template-columns: 1.2fr 1fr;
  }
}
.hero-title {
  font-size: var(--text-2xl);
  max-width: 20ch;
  margin-bottom: var(--space-4);
}
.hero-title em {
  font-style: normal;
  color: var(--color-primary);
}
.hero-lede {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 56ch;
  margin-bottom: var(--space-6);
}
.hero-actions {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.hero-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
}
.hero-panel-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-4);
}
.hero-compare-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  padding-block: var(--space-3);
  border-bottom: 1px solid var(--color-divider);
  gap: var(--space-3);
}
.hero-compare-row:last-child {
  border-bottom: none;
}
.hero-compare-row .label {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}
.hero-compare-row .value {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--text-base);
}
.hero-compare-row .value.tag-self {
  color: var(--color-primary);
}
.hero-compare-row .value.tag-cloud {
  color: var(--color-amber);
}

/* KPI strip */
.kpi-strip {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
  margin-top: var(--space-10);
}
@media (min-width: 720px) {
  .kpi-strip {
    grid-template-columns: repeat(4, 1fr);
  }
}
.kpi-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}
.kpi-card .kpi-value {
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: 700;
  display: block;
  margin-bottom: var(--space-1);
}
.kpi-card .kpi-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

/* ============================================================
   LEGEND / BADGES
   ============================================================ */
.legend-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-bottom: var(--space-6);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}
.legend-item {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}
.legend-dot {
  width: 10px;
  height: 10px;
  border-radius: var(--radius-full);
  flex-shrink: 0;
}

.support-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-xs);
  font-weight: 600;
  padding: 3px var(--space-2);
  border-radius: var(--radius-full);
  white-space: nowrap;
}
.support-native {
  background: var(--color-success-highlight);
  color: var(--color-success);
}
.support-pipeline {
  background: var(--color-primary-highlight);
  color: var(--color-primary);
}
.support-partial {
  background: var(--color-amber-highlight);
  color: var(--color-amber);
}
.support-none {
  background: var(--color-error-highlight);
  color: var(--color-error);
}

.tool-pill {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 600;
  padding: 2px var(--space-3);
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border);
  white-space: nowrap;
}
.tool-pill .dot {
  width: 8px;
  height: 8px;
  border-radius: var(--radius-full);
  flex-shrink: 0;
}
.pill-self {
  background: var(--color-primary-highlight);
  color: var(--color-primary);
  border-color: transparent;
}
.pill-cloud {
  background: var(--color-amber-highlight);
  color: var(--color-amber);
  border-color: transparent;
}

/* ============================================================
   FEATURE MATRIX TABLE
   ============================================================ */
.matrix-scroll {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  overscroll-behavior: contain;
}
.matrix-table {
  min-width: 980px;
  font-size: var(--text-sm);
}
.matrix-table caption {
  text-align: left;
  padding: var(--space-4) var(--space-5) 0;
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}
.matrix-table th,
.matrix-table td {
  padding: var(--space-3) var(--space-4);
  text-align: left;
  border-bottom: 1px solid var(--color-divider);
  vertical-align: top;
}
.matrix-table thead th {
  position: sticky;
  top: 0;
  background: var(--color-surface-2);
  z-index: 2;
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
  border-bottom: 1px solid var(--color-border);
}
.matrix-table thead th:first-child {
  z-index: 3;
}
.matrix-table td:first-child,
.matrix-table th:first-child {
  position: sticky;
  left: 0;
  background: var(--color-surface);
  font-weight: 600;
  color: var(--color-text);
  min-width: 190px;
  box-shadow: 1px 0 0 var(--color-border);
}
.matrix-table thead th:first-child {
  background: var(--color-surface-2);
}
.matrix-table tbody tr:hover td {
  background: var(--color-surface-offset);
}
.matrix-table tbody tr:hover td:first-child {
  background: var(--color-surface-offset);
}
.matrix-group-row td {
  background: var(--color-surface-2);
  color: var(--color-text-faint);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding-block: var(--space-2);
  font-weight: 600;
}
.matrix-group-row td:first-child {
  background: var(--color-surface-2);
}
.cell-sub {
  display: block;
  color: var(--color-text-faint);
  font-size: var(--text-xs);
  margin-top: 2px;
}

/* ============================================================
   CARD GRIDS (chart cards, tier cards)
   ============================================================ */
.grid-2 {
  display: grid;
  gap: var(--space-5);
}
@media (min-width: 860px) {
  .grid-2 {
    grid-template-columns: 1fr 1fr;
  }
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
}
.card-title {
  font-size: var(--text-base);
  font-weight: 650;
  margin-bottom: var(--space-1);
}
.card-sub {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  margin-bottom: var(--space-5);
}
.chart-wrap {
  position: relative;
  height: 300px;
}
.chart-wrap.tall {
  height: 360px;
}

.callout {
  display: flex;
  gap: var(--space-3);
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  margin-top: var(--space-6);
}
.callout svg {
  color: var(--color-primary);
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  margin-top: 2px;
}
.callout p,
.callout strong {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}
.callout strong {
  color: var(--color-text);
}

/* Tier / cost cards */
.tier-grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: repeat(auto-fill, minmax(min(260px, 100%), 1fr));
}
.tier-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.tier-card-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--space-2);
}
.tier-name {
  font-weight: 650;
  font-size: var(--text-sm);
}
.tier-cost {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
}
.tier-cost span {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  font-weight: 500;
}
.tier-specs {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}
.tier-specs .row {
  display: flex;
  justify-content: space-between;
  gap: var(--space-2);
}
.tier-specs .row span:last-child {
  font-family: var(--font-mono);
  color: var(--color-text);
}

/* ============================================================
   CALCULATOR
   ============================================================ */
.calc-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}
.calc-grid {
  display: grid;
  gap: 0;
}
@media (min-width: 960px) {
  .calc-grid {
    grid-template-columns: 340px 1fr;
  }
}
.calc-controls {
  padding: var(--space-6);
  background: var(--color-surface-2);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}
@media (min-width: 960px) {
  .calc-controls {
    border-bottom: none;
    border-right: 1px solid var(--color-border);
  }
}
.calc-results {
  padding: var(--space-6);
}

.field {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}
.field label {
  font-size: var(--text-xs);
  font-weight: 650;
  color: var(--color-text);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: var(--space-2);
}
.field label .field-value {
  font-family: var(--font-mono);
  color: var(--color-primary);
  font-weight: 600;
}
.field-hint {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}

input[type='range'] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--color-surface-offset-2);
  outline-offset: 4px;
}
input[type='range']::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  border: 3px solid var(--color-surface);
  box-shadow: var(--shadow-sm);
  cursor: pointer;
}
input[type='range']::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  border: 3px solid var(--color-surface);
  cursor: pointer;
}

select,
.number-input {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: var(--text-sm);
  min-height: 44px;
}
select:focus,
.number-input:focus {
  border-color: var(--color-primary);
}

.field-toggle-group {
  display: flex;
  gap: var(--space-2);
}
.field-toggle {
  flex: 1;
  text-align: center;
  padding: var(--space-2) var(--space-2);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-text-muted);
  min-height: 44px;
}
.field-toggle[aria-pressed='true'] {
  background: var(--color-primary-highlight);
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.result-kpis {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}
@media (min-width: 640px) {
  .result-kpis {
    grid-template-columns: repeat(4, 1fr);
  }
}
.result-kpi {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  background: var(--color-surface-2);
}
.result-kpi .rk-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-bottom: var(--space-2);
  display: block;
}
.result-kpi .rk-value {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: 700;
  display: block;
}
.result-kpi.accent {
  border-color: var(--color-primary);
  background: var(--color-primary-highlight);
}
.result-kpi.accent .rk-value {
  color: var(--color-primary);
}
.result-kpi .rk-delta {
  font-size: var(--text-xs);
  font-weight: 600;
  margin-top: 2px;
  display: block;
}
.rk-delta.up {
  color: var(--color-success);
}
.rk-delta.down {
  color: var(--color-error);
}

.calc-chart-wrap {
  position: relative;
  height: 340px;
  margin-bottom: var(--space-4);
}

.calc-footnote {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  margin-top: var(--space-4);
}

/* ============================================================
   SOURCES / FOOTER
   ============================================================ */
.sources-grid {
  display: grid;
  gap: var(--space-2) var(--space-8);
  grid-template-columns: 1fr;
  font-size: var(--text-sm);
}
@media (min-width: 760px) {
  .sources-grid {
    grid-template-columns: 1fr 1fr;
  }
}
.sources-grid li {
  padding-block: var(--space-2);
  border-bottom: 1px solid var(--color-divider);
  color: var(--color-text-muted);
}
.sources-grid li a {
  color: var(--color-text);
  font-weight: 500;
}

.site-footer {
  padding-block: var(--space-10);
}
.footer-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-6);
  align-items: center;
}
.footer-note {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  max-width: 60ch;
}

@media (min-width: 720px) {
  .kpi-strip.result-kpis {
    grid-template-columns: repeat(4, 1fr);
  }
}