/* ============================================================
   AVIATION DECODED — REVENUE MANAGEMENT SIMULATOR
   Quiet-luxury, Swiss-aviation design language.
   ============================================================ */

:root {
  /* surfaces */
  --paper:#F6F5F1; --canvas:#FBFAF7;
  --navy:#0B1E33; --navy-900:#081827; --navy-950:#06121F; --navy-50:#E7ECF2;
  /* text */
  --graphite:#2B313A; --muted:#5B636E;
  /* lines + accents */
  --line:#E2E0D9; --line-dark:#1C3047;
  --steel:#5E7E9B; --ice:#9DBCD4; --champagne:#C9B78E; --silver:#C7CBD1;
  /* data semantics (charts only) */
  --pos:#3E8C7E; --neg:#C06B5A;
  /* type */
  --font-sans:'Inter',ui-sans-serif,system-ui,-apple-system,sans-serif;
  --font-serif:'Newsreader',ui-serif,Georgia,serif;
  --font-mono:'IBM Plex Mono',ui-monospace,'SFMono-Regular',monospace;
  /* shape + motion */
  --radius:12px; --radius-sm:8px; --ease:cubic-bezier(.22,1,.36,1);
  --shadow-card:0 1px 2px rgba(11,30,51,.04),0 12px 32px -20px rgba(11,30,51,.18);
  --shadow-card-hover:0 2px 4px rgba(11,30,51,.05),0 22px 48px -24px rgba(11,30,51,.26);
  --container:1200px;
}

/* ── Reset ─────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 84px; }
body {
  background: var(--paper);
  color: var(--graphite);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
}
img, svg { display: block; max-width: 100%; }
button { cursor: pointer; font-family: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
input { font-family: inherit; }

/* ── Layout primitives ─────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.5rem;
}
@media (min-width: 900px) { .container { padding: 0 2rem; } }

.section { padding: 6rem 0; border-top: 1px solid var(--line); }
.section-canvas { background: var(--canvas); }
@media (min-width: 900px) { .section { padding: 8rem 0; } }

/* faint grid textures */
.bg-grid-dark {
  background-color: var(--navy);
  background-image:
    linear-gradient(rgba(157,188,212,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(157,188,212,0.05) 1px, transparent 1px);
  background-size: 64px 64px;
}

/* ── Typography ────────────────────────────────────────────── */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--steel);
}
.eyebrow-tick {
  display: inline-block;
  width: 16px;
  height: 1px;
  background: var(--steel);
}
.eyebrow-on-dark { color: var(--ice); }
.eyebrow-on-dark .eyebrow-tick { background: var(--ice); }

.section-heading { margin-bottom: 3rem; max-width: 46rem; }
.section-title {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(1.8rem, 3.6vw, 2.75rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--navy);
  margin-top: 1rem;
  text-wrap: balance;
}
.section-intro {
  margin-top: 1.1rem;
  color: var(--muted);
  font-size: 1.0625rem;
  max-width: 60ch;
}

.prose { max-width: 68ch; }
.prose p { color: var(--muted); font-size: 1.0625rem; }
.prose p + p { margin-top: 1.25rem; }

/* ── Buttons ───────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  height: 44px;
  padding: 0 1.4rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  transition: transform 0.4s var(--ease), background 0.3s var(--ease), border-color 0.3s var(--ease), color 0.3s var(--ease);
  white-space: nowrap;
}
.btn:hover { transform: translateY(-1px); }
.btn-sm { height: 32px; padding: 0 0.85rem; font-size: 0.78rem; }
.btn-primary { background: var(--navy); color: var(--paper); }
.btn-primary:hover { background: var(--navy-900); }
.btn-secondary { background: transparent; border-color: var(--line); color: var(--navy); }
.btn-secondary:hover { border-color: var(--steel); }
.btn-champagne { background: var(--champagne); color: var(--navy-950); }
.btn-champagne:hover { background: #d4c39c; }
.btn-ghost { background: transparent; color: var(--muted); border-color: var(--line); }
.btn-ghost:hover { color: var(--navy); border-color: var(--steel); }
.btn-ghost-light { background: transparent; color: var(--navy-50); border-color: var(--line-dark); }
.btn-ghost-light:hover { border-color: var(--ice); color: #fff; }
.btn .icon-sm { width: 16px; height: 16px; }

/* ── Pills & tags ──────────────────────────────────────────── */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--line-dark);
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--navy-50);
}
.pill-dot { width: 5px; height: 5px; border-radius: 50%; background: currentColor; }
.pill-champagne { color: var(--champagne); border-color: rgba(201,183,142,0.4); }

.tag {
  font-family: var(--font-mono);
  font-size: 0.64rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--ice);
  padding: 0.3rem 0.6rem;
  border: 1px solid var(--line-dark);
  border-radius: 6px;
}

/* ── Icons ─────────────────────────────────────────────────── */
.icon { width: 20px; height: 20px; }
.icon-sm { width: 16px; height: 16px; }

/* ── Masthead ──────────────────────────────────────────────── */
.masthead {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(246,245,241,0.86);
  backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.masthead-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.masthead-brand { display: flex; align-items: center; gap: 0.7rem; }
.masthead-brand img { height: 26px; width: auto; }
.masthead-brand-divider { width: 1px; height: 22px; background: var(--line); }
.masthead-brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.masthead-brand-text small {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}
.masthead-nav { display: flex; align-items: center; gap: 1.6rem; }
.masthead-nav a {
  font-size: 0.85rem;
  color: var(--muted);
  transition: color 0.3s var(--ease);
}
.masthead-nav a:hover { color: var(--navy); }
.masthead-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.45rem 0.9rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--navy) !important;
}
.masthead-cta:hover { border-color: var(--steel); }
@media (max-width: 720px) {
  .masthead-nav a:not(.masthead-cta) { display: none; }
}
@media (max-width: 520px) {
  .masthead-brand-divider, .masthead-brand-text { display: none; }
  .masthead-cta { padding: 0.4rem 0.8rem; font-size: 0.8rem; }
  .masthead-cta .icon-sm { display: none; }
}

/* ── Hero ──────────────────────────────────────────────────── */
.hero { color: var(--navy-50); padding: 5rem 0; overflow: hidden; }
@media (min-width: 900px) { .hero { padding: 7rem 0; } }
.hero-inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  align-items: center;
}
@media (min-width: 980px) {
  .hero-inner { grid-template-columns: 1.05fr 0.95fr; gap: 4rem; }
}
.hero-meta { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; margin-bottom: 1.6rem; }
.hero-category {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--steel);
}
.hero-title {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(2.4rem, 6vw, 4.2rem);
  line-height: 1.02;
  letter-spacing: -0.03em;
  color: #fff;
  text-wrap: balance;
}
.hero-subtitle {
  margin-top: 1.5rem;
  font-size: 1.15rem;
  line-height: 1.55;
  color: var(--navy-50);
  max-width: 36ch;
  opacity: 0.86;
}
.hero-tags { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 1.8rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.8rem; margin-top: 2.2rem; }
.hero-stage { display: flex; flex-direction: column; gap: 1rem; justify-content: center; align-items: center; }
.hero-visual { width: 100%; max-width: 460px; }
.hero-caption {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--steel);
  text-align: center;
  max-width: 36ch;
}
.hero-mono { font-family: var(--font-mono); font-size: 9px; letter-spacing: 0.1em; }

/* breadcrumb + code + meta block */
.hero-breadcrumb {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--steel);
  margin-bottom: 2.4rem;
}
.hero-breadcrumb a { color: var(--steel); transition: color 0.3s var(--ease); }
.hero-breadcrumb a:hover { color: var(--ice); }
.hero-meta-top { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; margin-bottom: 1.6rem; }
.hero-code {
  margin-top: 1rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--champagne);
}
.hero-spec {
  display: flex;
  flex-wrap: wrap;
  gap: 2.4rem;
  margin-top: 2.4rem;
  padding-top: 1.8rem;
  border-top: 1px solid var(--line-dark);
}
.hero-spec-item { display: flex; flex-direction: column; gap: 0.4rem; }
.hero-spec-item dt {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--steel);
}
.hero-spec-item dd { font-size: 0.95rem; color: var(--navy-50); }

/* lead prose + demonstrates list */
.prose-lead p { font-size: 1.2rem; line-height: 1.6; color: var(--graphite); }
.prose-lead p + p { margin-top: 1.4rem; color: var(--muted); }
.demo-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem 2.4rem;
  max-width: 760px;
}
@media (min-width: 680px) { .demo-list { grid-template-columns: 1fr 1fr; } }
.demo-item {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  font-size: 1.05rem;
  color: var(--graphite);
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--line);
}
.demo-tick {
  width: 6px; height: 6px;
  flex-shrink: 0;
  border-radius: 50%;
  background: var(--champagne);
  transform: translateY(-2px);
}

/* ── Concepts ──────────────────────────────────────────────── */
.concept-grid {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: 1.25rem;
}
@media (min-width: 640px) { .concept-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .concept-grid { grid-template-columns: repeat(4, 1fr); } }
.concept-card {
  background: var(--canvas);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.6rem 1.4rem;
  transition: transform 0.5s var(--ease), box-shadow 0.5s var(--ease), border-color 0.5s var(--ease);
}
.concept-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-card-hover);
  border-color: var(--silver);
}
.concept-index {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--champagne);
}
.concept-title {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 1.2rem;
  line-height: 1.2;
  color: var(--navy);
  margin: 0.7rem 0 0.6rem;
  letter-spacing: -0.01em;
}
.concept-body { font-size: 0.92rem; color: var(--muted); line-height: 1.55; }

/* ── Simulator surface ─────────────────────────────────────── */
.simulator-surface { margin-top: 0.5rem; }

/* Scenario selector */
.scenario-selector { margin-bottom: 2rem; }
.scenario-head { margin-bottom: 0.9rem; }
.scenario-pills { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.scenario-pill {
  padding: 0.5rem 0.95rem;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--paper);
  font-size: 0.82rem;
  color: var(--muted);
  transition: all 0.3s var(--ease);
}
.scenario-pill:hover { border-color: var(--steel); color: var(--navy); }
.scenario-pill.active {
  background: var(--navy);
  border-color: var(--navy);
  color: var(--paper);
}
.scenario-lesson {
  margin-top: 1rem;
  font-size: 0.95rem;
  color: var(--muted);
  max-width: 70ch;
  padding-left: 1rem;
  border-left: 2px solid var(--champagne);
}

/* Sim grid */
.sim-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}
@media (min-width: 1040px) {
  .sim-grid { grid-template-columns: 380px 1fr; align-items: start; }
}
.sim-controls-col { display: flex; flex-direction: column; gap: 1.25rem; }
.sim-output-col { display: flex; flex-direction: column; gap: 1.25rem; }

/* Panels */
.panel {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-card);
}
.section-canvas .panel { background: var(--paper); }
.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.3rem;
}

/* Controls */
.control-stack { display: flex; flex-direction: column; gap: 1.4rem; }
.control { display: flex; flex-direction: column; gap: 0.5rem; }
.control-row { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; }
.control label { font-size: 0.88rem; font-weight: 500; color: var(--navy); }
.control-value {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--steel);
  font-variant-numeric: tabular-nums;
}
.control-help { font-size: 0.76rem; color: var(--muted); line-height: 1.45; }

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 2px;
  background: var(--line);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--navy);
  border: 2px solid var(--paper);
  box-shadow: 0 1px 4px rgba(11,30,51,0.25);
  transition: transform 0.2s var(--ease);
}
input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.15); }
input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--navy);
  border: 2px solid var(--paper);
  cursor: pointer;
}
input[type="range"]:focus-visible::-webkit-slider-thumb { box-shadow: 0 0 0 4px rgba(94,126,155,0.3); }

/* ── Fare table ────────────────────────────────────────────── */
.fare-table-wrap { overflow-x: auto; }
.fare-table { width: 100%; border-collapse: collapse; font-size: 0.85rem; }
.fare-table thead th {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
  text-align: left;
  padding: 0 0.5rem 0.7rem;
  border-bottom: 1px solid var(--line);
}
.fare-table td {
  padding: 0.6rem 0.5rem;
  border-bottom: 1px solid var(--line);
  vertical-align: middle;
}
.fare-table tbody tr:last-child td { border-bottom: 1px solid var(--line); }
.fc-code {
  font-family: var(--font-mono);
  font-weight: 500;
  color: var(--navy);
  width: 2.2rem;
}
.fc-name { color: var(--graphite); line-height: 1.2; }
.fc-timing {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin-top: 2px;
}
.fc-num { text-align: right; font-variant-numeric: tabular-nums; font-family: var(--font-mono); font-size: 0.82rem; }
.fc-sold { color: var(--pos); font-weight: 500; }
.fc-spill { color: var(--neg); }
.fc-input input {
  width: 4.6rem;
  padding: 0.35rem 0.45rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--canvas);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  text-align: right;
  color: var(--navy);
  transition: border-color 0.2s var(--ease);
}
.fc-input input:focus { outline: none; border-color: var(--steel); box-shadow: 0 0 0 3px rgba(94,126,155,0.14); }
.fare-table tfoot td {
  padding-top: 0.8rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--navy);
  border-bottom: none;
}
.fc-foot-label { text-align: right; text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.62rem; color: var(--muted); }
.fare-table-note { margin-top: 0.9rem; font-size: 0.74rem; color: var(--muted); line-height: 1.5; }
.fare-table-note strong { color: var(--graphite); font-weight: 600; }

/* ── KPI tiles ─────────────────────────────────────────────── */
.metrics-panel {}
.kpi-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
@media (min-width: 720px) { .kpi-grid { grid-template-columns: repeat(4, 1fr); } }
.kpi-tile {
  background: var(--paper);
  padding: 1.1rem 1.2rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  min-height: 96px;
}
.kpi-value {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 1.55rem;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--navy);
  font-variant-numeric: tabular-nums;
}
.kpi-label {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
  margin-top: 0.35rem;
}
.kpi-sub { font-family: var(--font-mono); font-size: 0.66rem; color: var(--silver); letter-spacing: 0.04em; }
.kpi-headline { background: var(--navy); }
.kpi-headline .kpi-value { color: #fff; }
.kpi-headline .kpi-label { color: var(--ice); }
.kpi-headline .kpi-sub { color: var(--steel); }
.kpi-neg .kpi-value { color: var(--neg); }

/* ── Charts ────────────────────────────────────────────────── */
.chart-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}
@media (min-width: 720px) { .chart-row { grid-template-columns: 1fr 1fr; } }
.chart-card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.3rem;
  box-shadow: var(--shadow-card);
}
.chart-card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.8rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}
.chart-legend-row {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}
.legend-swatch { width: 10px; height: 10px; border-radius: 2px; display: inline-block; }
.legend-swatch.legend-current { background: var(--steel); }
.legend-swatch.legend-best { background: var(--champagne); margin-left: 0.6rem; }
.legend-line { width: 14px; height: 0; border-top: 2px solid; display: inline-block; }
.legend-line.legend-demand { border-color: var(--silver); }
.legend-line.legend-sold { border-color: var(--steel); margin-left: 0.6rem; }
.chart-svg { width: 100%; height: auto; }
.chart-caption { margin-top: 0.9rem; font-size: 0.78rem; color: var(--muted); line-height: 1.5; }
.chart-caption strong { color: var(--navy); font-weight: 600; }

/* svg chart internals */
.chart-axis { stroke: var(--line); stroke-width: 1; }
.chart-mono { font-family: var(--font-mono); font-size: 9px; fill: var(--muted); letter-spacing: 0.04em; }
.chart-axis-title { fill: var(--silver); font-size: 8px; letter-spacing: 0.12em; }
.rc-bar { fill: var(--steel); opacity: 0.32; transition: opacity 0.3s var(--ease); }
.rc-bar-current { opacity: 0.85; }
.rc-bar-best { fill: var(--champagne); opacity: 1; }
.chart-ref { stroke: var(--line); stroke-width: 1; stroke-dasharray: 3 3; }
.chart-ref-strong { stroke: var(--steel); stroke-dasharray: none; opacity: 0.5; }
.chart-ref-label { fill: var(--silver); font-size: 8px; letter-spacing: 0.1em; }
.bc-demand-area { fill: rgba(157,188,212,0.12); }
.bc-demand-line { stroke: var(--silver); stroke-width: 1.3; fill: none; }
.bc-sold-line { stroke: var(--steel); stroke-width: 1.6; fill: none; }
.bc-node { fill: var(--steel); }

/* ── Explanation panel ─────────────────────────────────────── */
.explain-panel {
  background: var(--navy);
  border-radius: var(--radius);
  padding: 1.8rem;
  color: var(--navy-50);
}
.explain-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.2rem;
}
.explain-stance {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--line-dark);
}
.explain-stance-good { color: var(--pos); border-color: rgba(62,140,126,0.5); }
.explain-stance-warn { color: var(--champagne); border-color: rgba(201,183,142,0.5); }
.explain-stance-neutral { color: var(--ice); }
.explain-headline {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 1.3rem;
  line-height: 1.3;
  color: #fff;
  letter-spacing: -0.01em;
  margin-bottom: 1.4rem;
  text-wrap: balance;
}
.explain-rows { display: flex; flex-direction: column; gap: 1rem; }
.explain-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.3rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--line-dark);
}
@media (min-width: 560px) { .explain-row { grid-template-columns: 130px 1fr; gap: 1.2rem; } }
.explain-label {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--steel);
  padding-top: 2px;
}
.explain-text { font-size: 0.9rem; line-height: 1.55; color: var(--navy-50); opacity: 0.9; }
.explain-action {
  margin-top: 1.4rem;
  padding: 1.1rem 1.2rem;
  background: rgba(201,183,142,0.08);
  border: 1px solid rgba(201,183,142,0.25);
  border-radius: var(--radius-sm);
}
.explain-action-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--champagne);
  margin-bottom: 0.5rem;
}
.explain-action p { font-size: 0.92rem; line-height: 1.55; color: #fff; }

/* ── CTA ───────────────────────────────────────────────────── */
.cta { color: var(--navy-50); padding: 6rem 0; border-top: 1px solid var(--line-dark); }
.cta-inner { max-width: 42rem; }
.cta-title {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: #fff;
  margin: 1rem 0 1.1rem;
  text-wrap: balance;
}
.cta-body { color: var(--navy-50); opacity: 0.85; font-size: 1.05rem; max-width: 52ch; }
.cta-actions { display: flex; flex-wrap: wrap; gap: 0.8rem; margin-top: 2rem; }

/* ── Footer ────────────────────────────────────────────────── */
.site-footer { background: var(--navy-950); padding: 2.2rem 0; }
.site-footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.footer-brand { font-family: var(--font-serif); font-size: 1.05rem; color: var(--navy-50); }
.footer-meta { font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.06em; color: var(--steel); text-transform: uppercase; }

/* ── Motion ────────────────────────────────────────────────── */
.fade-up { opacity: 0; transform: translateY(12px); transition: opacity 0.7s var(--ease), transform 0.7s var(--ease); }
.fade-up.in-view { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; }
  .fade-up { opacity: 1; transform: none; }
}

/* ============================================================
   SIMULATOR APP
   ============================================================ */

/* ── Masthead stage indicator ──────────────────────────────── */
.sim-stages { display: flex; align-items: center; gap: 1.2rem; }
.sim-stage {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--silver);
}
.sim-stage-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--line); }
.sim-stage.active { color: var(--navy); }
.sim-stage.active .sim-stage-dot { background: var(--champagne); }
.sim-stage.done { color: var(--muted); }
.sim-stage.done .sim-stage-dot { background: var(--steel); }
@media (max-width: 820px) { .sim-stage { display: none; } }

/* ── Intro / mode select ───────────────────────────────────── */
.sim-intro { padding-bottom: 4rem; }
.sim-intro-inner { max-width: 56rem; }
.sim-intro-inner .pill { margin-bottom: 1.4rem; }
.mode-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
  margin-top: 3rem;
}
@media (min-width: 760px) { .mode-grid { grid-template-columns: 1fr 1fr; } }
.mode-card {
  text-align: left;
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--line-dark);
  border-radius: var(--radius);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  transition: transform 0.4s var(--ease), border-color 0.4s var(--ease), background 0.4s var(--ease);
}
.mode-card:hover { transform: translateY(-3px); border-color: var(--steel); background: rgba(255,255,255,0.06); }
.mode-num { font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.16em; color: var(--champagne); }
.mode-card h2 { font-family: var(--font-serif); font-weight: 500; font-size: 1.5rem; color: #fff; letter-spacing: -0.01em; }
.mode-card p { font-size: 0.95rem; color: var(--navy-50); opacity: 0.82; line-height: 1.55; flex: 1; }
.mode-cta {
  display: inline-flex; align-items: center; gap: 0.4rem;
  margin-top: 0.8rem;
  font-size: 0.85rem; font-weight: 500; color: var(--ice);
}

/* ── Learn walkthrough ─────────────────────────────────────── */
.learn-section { padding-top: 3rem; }
.learn-container {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: start;
}
@media (min-width: 940px) { .learn-container { grid-template-columns: 250px 1fr; gap: 3.5rem; } }
.learn-rail { position: sticky; top: 88px; display: flex; flex-direction: column; gap: 0.3rem; }
.learn-rail .eyebrow { margin-bottom: 0.8rem; }
.learn-toc { display: flex; flex-direction: column; gap: 0.1rem; margin-bottom: 1.2rem; }
.learn-toc-item {
  display: flex; align-items: baseline; gap: 0.7rem;
  width: 100%; text-align: left;
  padding: 0.55rem 0.6rem;
  border-radius: var(--radius-sm);
  background: transparent; border: none;
  color: var(--muted); font-size: 0.85rem;
  transition: background 0.25s var(--ease), color 0.25s var(--ease);
}
.learn-toc-item:hover { background: var(--canvas); color: var(--navy); }
.learn-toc-item.current { background: var(--navy); color: #fff; }
.learn-toc-item.done { color: var(--graphite); }
.learn-toc-num { font-family: var(--font-mono); font-size: 0.7rem; color: var(--champagne); flex-shrink: 0; }
.learn-toc-item.current .learn-toc-num { color: var(--champagne); }
.learn-toc-title { line-height: 1.2; }
@media (max-width: 939px) { .learn-rail { position: static; } .learn-toc { display: none; } }

.learn-main { max-width: 44rem; }
.learn-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 0.8rem; }
.learn-kicker { font-family: var(--font-mono); font-size: 0.66rem; text-transform: uppercase; letter-spacing: 0.18em; color: var(--steel); }
.learn-progress { font-family: var(--font-mono); font-size: 0.72rem; color: var(--silver); }
.learn-title {
  font-family: var(--font-serif); font-weight: 500;
  font-size: clamp(1.9rem, 4vw, 2.8rem); line-height: 1.08;
  letter-spacing: -0.02em; color: var(--navy);
  margin-bottom: 1.4rem; text-wrap: balance;
}
.learn-body p { font-size: 1.08rem; line-height: 1.65; color: var(--muted); }
.learn-body p + p { margin-top: 1.1rem; }

.formula-card {
  background: var(--navy);
  border-radius: var(--radius);
  padding: 1.6rem 1.8rem;
  margin: 2rem 0;
}
.formula-label {
  display: block;
  font-family: var(--font-mono); font-size: 0.62rem;
  text-transform: uppercase; letter-spacing: 0.14em;
  color: var(--ice); margin-bottom: 0.9rem;
}
.formula-expr {
  display: block;
  font-family: var(--font-mono); font-size: 1.05rem;
  color: var(--champagne); background: transparent;
  border: none; padding: 0; line-height: 1.5;
  margin-bottom: 1.1rem; white-space: pre-wrap;
}
.formula-legend { display: flex; flex-direction: column; gap: 0.4rem; }
.formula-legend li {
  font-family: var(--font-mono); font-size: 0.76rem;
  color: var(--navy-50); opacity: 0.75; line-height: 1.45;
  padding-left: 1rem; position: relative;
}
.formula-legend li::before { content: "·"; position: absolute; left: 0.2rem; color: var(--steel); }

.learn-example {
  border-left: 2px solid var(--champagne);
  padding: 0.2rem 0 0.2rem 1.2rem;
  margin: 1.8rem 0;
}
.learn-example-label { display: block; font-family: var(--font-mono); font-size: 0.62rem; text-transform: uppercase; letter-spacing: 0.14em; color: var(--steel); margin-bottom: 0.4rem; }
.learn-example p { font-size: 0.98rem; color: var(--graphite); line-height: 1.6; }
.learn-takeaway {
  font-family: var(--font-serif); font-style: italic;
  font-size: 1.25rem; line-height: 1.4; color: var(--navy);
  margin: 1.8rem 0; text-wrap: balance;
}
.learn-nav { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin-top: 2.5rem; padding-top: 1.6rem; border-top: 1px solid var(--line); }
.learn-skip { align-self: flex-start; }
.is-hidden { visibility: hidden; }

/* ── Scenario cards ────────────────────────────────────────── */
.scenario-card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}
@media (min-width: 680px) { .scenario-card-grid { grid-template-columns: 1fr 1fr; } }
@media (min-width: 1040px) { .scenario-card-grid { grid-template-columns: repeat(3, 1fr); } }
.scenario-card {
  text-align: left;
  background: var(--canvas);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.6rem;
  display: flex; flex-direction: column; gap: 0.7rem;
  box-shadow: var(--shadow-card);
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease), border-color 0.4s var(--ease);
}
.scenario-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-card-hover); border-color: var(--silver); }
.scenario-card-head { display: flex; align-items: center; justify-content: space-between; }
.scenario-diff { font-family: var(--font-mono); font-size: 0.62rem; text-transform: uppercase; letter-spacing: 0.12em; color: var(--champagne); }
.route-pill { font-family: var(--font-mono); font-size: 0.64rem; color: var(--muted); border: 1px solid var(--line); border-radius: 999px; padding: 0.2rem 0.6rem; }
.scenario-card h3 { font-family: var(--font-serif); font-weight: 500; font-size: 1.3rem; color: var(--navy); letter-spacing: -0.01em; }
.scenario-card p { font-size: 0.9rem; color: var(--muted); line-height: 1.5; flex: 1; }
.scenario-fares { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.fare-chip { font-family: var(--font-mono); font-size: 0.66rem; color: var(--graphite); background: var(--paper); border: 1px solid var(--line); border-radius: 6px; padding: 0.2rem 0.5rem; }
.fare-chip strong { color: var(--navy); }
.scenario-card-cta { display: inline-flex; align-items: center; gap: 0.4rem; margin-top: 0.5rem; font-size: 0.85rem; font-weight: 500; color: var(--steel); }

/* ── Play view ─────────────────────────────────────────────── */
.play-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 1rem; margin-bottom: 1.6rem; }
.play-title { font-family: var(--font-serif); font-weight: 500; font-size: clamp(1.5rem, 3vw, 2.1rem); color: var(--navy); letter-spacing: -0.01em; margin-top: 0.4rem; }

.cp-timeline { display: flex; align-items: center; margin-bottom: 2rem; }
.cp-node { display: flex; flex-direction: column; align-items: center; gap: 0.4rem; flex-shrink: 0; }
.cp-dot { width: 11px; height: 11px; border-radius: 50%; background: var(--line); border: 2px solid var(--paper); box-shadow: 0 0 0 1px var(--line); }
.cp-label { font-family: var(--font-mono); font-size: 0.6rem; color: var(--silver); letter-spacing: 0.06em; }
.cp-node.done .cp-dot { background: var(--steel); box-shadow: 0 0 0 1px var(--steel); }
.cp-node.done .cp-label { color: var(--muted); }
.cp-node.current .cp-dot { background: var(--champagne); box-shadow: 0 0 0 1px var(--champagne); transform: scale(1.25); }
.cp-node.current .cp-label { color: var(--navy); font-weight: 500; }
.cp-line { flex: 1; height: 1px; background: var(--line); margin: 0 0.3rem; margin-bottom: 1.1rem; }

.flight-status {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 0.8rem;
}
@media (min-width: 760px) { .flight-status { grid-template-columns: repeat(5, 1fr); } }
.status-tile { background: var(--paper); padding: 0.9rem 1.1rem; display: flex; flex-direction: column; gap: 0.3rem; }
.status-tile span { font-family: var(--font-mono); font-size: 0.58rem; text-transform: uppercase; letter-spacing: 0.1em; color: var(--muted); }
.status-tile strong { font-family: var(--font-serif); font-weight: 500; font-size: 1.35rem; color: var(--navy); }
.status-tile strong small { font-size: 0.8rem; color: var(--silver); }
.status-pace { font-size: 1rem !important; }

.sold-bar { display: flex; height: 10px; width: 100%; background: var(--surface-2, #eef0ee); border-radius: 999px; overflow: hidden; margin-bottom: 2rem; border: 1px solid var(--line); }
.sold-seg { display: block; height: 100%; }

.play-grid { display: grid; grid-template-columns: 1fr; gap: 1.5rem; align-items: start; }
@media (min-width: 940px) { .play-grid { grid-template-columns: 1fr 1fr; } }
.play-instruction { font-size: 0.9rem; color: var(--muted); line-height: 1.55; margin-bottom: 1.4rem; }
.play-instruction strong { color: var(--navy); }

.bid-class-list { display: flex; flex-direction: column; margin: 1.2rem 0; border: 1px solid var(--line); border-radius: var(--radius-sm); overflow: hidden; }
.bid-class-row {
  display: grid;
  grid-template-columns: 2rem 1fr auto auto auto;
  gap: 0.6rem; align-items: center;
  padding: 0.55rem 0.8rem;
  font-size: 0.8rem;
  border-bottom: 1px solid var(--line);
}
.bid-class-row:last-child { border-bottom: none; }
.bid-class-code { font-family: var(--font-mono); font-weight: 500; color: var(--navy); }
.bid-class-name { color: var(--muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.bid-class-price { font-family: var(--font-mono); color: var(--graphite); }
.bid-class-status { font-family: var(--font-mono); font-size: 0.62rem; text-transform: uppercase; letter-spacing: 0.08em; padding: 0.15rem 0.5rem; border-radius: 999px; }
.bid-class-sold { font-family: var(--font-mono); font-size: 0.7rem; color: var(--silver); text-align: right; }
.bid-class-row.open { background: rgba(62,140,126,0.05); }
.bid-class-row.open .bid-class-status { color: var(--pos); background: rgba(62,140,126,0.12); }
.bid-class-row.closed { opacity: 0.6; }
.bid-class-row.closed .bid-class-status { color: var(--neg); background: rgba(192,107,90,0.12); }

.play-actions { display: flex; align-items: center; gap: 0.8rem; flex-wrap: wrap; margin-top: 0.4rem; }
.play-hint { display: flex; gap: 0.7rem; align-items: flex-start; margin-top: 1.2rem; padding: 0.9rem 1.1rem; background: var(--canvas); border: 1px solid var(--line); border-left: 2px solid var(--champagne); border-radius: var(--radius-sm); }
.play-hint .icon { color: var(--steel); flex-shrink: 0; margin-top: 2px; }
.play-hint p { font-size: 0.85rem; color: var(--graphite); line-height: 1.5; }

.play-log-empty { font-size: 0.9rem; color: var(--muted); line-height: 1.55; }
.play-log-table { font-size: 0.8rem; }
.pace-chip { display: inline-flex; align-items: center; gap: 0.4rem; font-family: var(--font-sans); font-size: 0.72rem; font-weight: 500; padding: 0.2rem 0.55rem; border-radius: 999px; border: 1px solid var(--line); }
.pace-dot { width: 6px; height: 6px; border-radius: 50%; background: currentColor; }
.pace-pos { color: var(--pos); border-color: rgba(62,140,126,0.4); }
.pace-neg { color: var(--neg); border-color: rgba(192,107,90,0.4); }
.pace-neutral { color: var(--muted); }

/* ── Debrief ───────────────────────────────────────────────── */
.debrief-hero {
  background: var(--navy);
  border-radius: var(--radius);
  padding: 3rem 2rem;
  text-align: center;
  display: flex; flex-direction: column; align-items: center; gap: 1rem;
  margin-bottom: 1.5rem;
}
.debrief-hero .eyebrow { margin-bottom: 0.6rem; }
.star-row { display: inline-flex; gap: 0.4rem; }
.star { display: block; }
.debrief-score { font-family: var(--font-serif); font-weight: 500; font-size: 3rem; line-height: 1; color: #fff; }
.debrief-score span { font-size: 1.4rem; color: var(--steel); }
.debrief-verdict { font-family: var(--font-serif); font-size: 1.25rem; line-height: 1.4; color: var(--navy-50); max-width: 46ch; text-wrap: balance; }

.debrief-kpis { margin-bottom: 1.5rem; }
.debrief-grid { display: grid; grid-template-columns: 1fr; gap: 1.25rem; margin-bottom: 2rem; }
@media (min-width: 860px) { .debrief-grid { grid-template-columns: 1fr 1fr; } }

.cmp-list { display: flex; flex-direction: column; gap: 1rem; }
.cmp-row { display: grid; grid-template-columns: 1fr; gap: 0.4rem; }
.cmp-label { font-size: 0.82rem; color: var(--muted); }
.cmp-track { height: 8px; background: var(--surface-2, #eef0ee); border-radius: 999px; overflow: hidden; }
.cmp-fill { display: block; height: 100%; background: var(--steel); border-radius: 999px; transition: width 0.6s var(--ease); }
.cmp-fill-best { background: var(--champagne); }
.cmp-value { font-family: var(--font-mono); font-size: 0.78rem; color: var(--navy); text-align: right; margin-top: -1.4rem; }

.debrief-notes { display: flex; flex-direction: column; gap: 0.9rem; }
.debrief-notes li {
  font-size: 0.92rem; color: var(--graphite); line-height: 1.55;
  padding-left: 1.1rem; position: relative;
}
.debrief-notes li::before { content: "—"; position: absolute; left: 0; color: var(--champagne); }
.debrief-actions { display: flex; flex-wrap: wrap; gap: 0.8rem; }