:root {
  color-scheme: light;
  --bg: #f7f8fb;
  --panel: #ffffff;
  --text: #202430;
  --muted: #626978;
  --border: #dfe4eb;
  --accent: #2167a8;
  --accent-2: #d87832;
  --accent-soft: #eaf3fb;
  --good: #287a55;
  --bad: #b84a4a;
  --grid: #e8ebf0;
  --shadow: 0 16px 36px rgba(32, 36, 48, 0.07);
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #22252e;
  --panel: #292d38;
  --text: #f3f4f7;
  --muted: #b0b6c2;
  --border: #3a404d;
  --accent: #9fd0f6;
  --accent-2: #f0ad72;
  --accent-soft: #293b4c;
  --good: #78d5aa;
  --bad: #f09292;
  --grid: #353b47;
  --shadow: none;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #22252e;
    --panel: #292d38;
    --text: #f3f4f7;
    --muted: #b0b6c2;
    --border: #3a404d;
    --accent: #9fd0f6;
    --accent-2: #f0ad72;
    --accent-soft: #293b4c;
    --good: #78d5aa;
    --bad: #f09292;
    --grid: #353b47;
    --shadow: none;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  margin: 0;
}

.game-hero {
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  padding: clamp(1.35rem, 3vw, 2.15rem) clamp(1rem, 3vw, 2rem) 1.25rem;
}

.eyebrow {
  color: var(--accent);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  margin: 0 0 0.45rem;
  text-transform: uppercase;
}

h1 {
  font-size: clamp(1.7rem, 1.25rem + 2vw, 2.65rem);
  line-height: 1.08;
  margin: 0 0 0.65rem;
}

.subtitle {
  color: var(--muted);
  line-height: 1.55;
  margin: 0;
  max-width: 960px;
}

.equation {
  background: var(--accent-soft);
  border: 1px solid color-mix(in srgb, var(--accent) 22%, var(--border));
  border-radius: 0.75rem;
  color: var(--text);
  display: inline-block;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.88rem;
  margin-top: 0.85rem;
  padding: 0.5rem 0.72rem;
}

.game-wrap {
  display: grid;
  gap: 1rem;
  grid-template-columns: minmax(16rem, 21rem) minmax(0, 1fr);
  padding: 1rem;
}

.panel,
.stat,
.chart-card,
.lesson {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 0.85rem;
  box-shadow: var(--shadow);
}

.controls {
  align-self: start;
  padding: 1rem;
  position: sticky;
  top: 1rem;
}

.control { margin-bottom: 1.15rem; }

.control label {
  align-items: baseline;
  display: flex;
  font-size: 0.9rem;
  font-weight: 700;
  gap: 0.75rem;
  justify-content: space-between;
  margin-bottom: 0.45rem;
}

.control output {
  color: var(--accent);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

input[type="range"] {
  accent-color: var(--accent);
  cursor: pointer;
  width: 100%;
}

.button-row {
  display: grid;
  gap: 0.5rem;
  grid-template-columns: 1fr 1fr;
  margin-top: 0.3rem;
}

.button-row.three {
  grid-template-columns: repeat(3, 1fr);
}

button {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 0.65rem;
  color: var(--text);
  cursor: pointer;
  font: inherit;
  font-size: 0.86rem;
  font-weight: 750;
  min-height: 2.7rem;
  padding: 0.65rem 0.8rem;
}

button:hover { border-color: var(--accent); }

button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--bg);
}

.note {
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.5;
  margin: 1rem 0 0;
}

.stage { min-width: 0; }

.stats {
  display: grid;
  gap: 0.7rem;
  grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
  margin-bottom: 0.8rem;
}

.stat { padding: 0.9rem; }

.stat-label {
  color: var(--muted);
  font-size: 0.68rem;
  font-weight: 760;
  letter-spacing: 0.055em;
  line-height: 1.25;
  text-transform: uppercase;
}

.stat-value {
  font-size: clamp(1.15rem, 1rem + 0.8vw, 1.65rem);
  font-variant-numeric: tabular-nums;
  font-weight: 780;
  line-height: 1.1;
  margin-top: 0.38rem;
}

.stat-value.good { color: var(--good); }
.stat-value.bad { color: var(--bad); }

.charts {
  display: grid;
  gap: 0.8rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.chart-card { min-width: 0; padding: 0.75rem; }

.chart-card.wide { grid-column: 1 / -1; }

.chart-title {
  font-size: 0.92rem;
  font-weight: 750;
  margin: 0 0 0.2rem 0.2rem;
}

.chart-caption {
  color: var(--muted);
  font-size: 0.74rem;
  line-height: 1.35;
  margin: 0 0 0.55rem 0.2rem;
}

canvas {
  display: block;
  height: 280px;
  width: 100%;
}

.lesson {
  border-left: 4px solid var(--accent-2);
  line-height: 1.55;
  margin-top: 0.8rem;
  padding: 0.9rem 1rem;
}

.lesson strong { color: var(--accent-2); }

.matrix {
  border-collapse: collapse;
  font-size: 0.82rem;
  margin-top: 0.8rem;
  width: 100%;
}

.matrix th,
.matrix td {
  border-bottom: 1px solid var(--border);
  padding: 0.5rem 0.35rem;
  text-align: right;
}

.matrix th:first-child,
.matrix td:first-child { text-align: left; }

.challenge {
  background: var(--accent-soft);
  border-radius: 0.65rem;
  font-size: 0.82rem;
  line-height: 1.45;
  margin: 0 0 1rem;
  padding: 0.75rem;
}

@media (max-width: 900px) {
  .game-wrap { grid-template-columns: 1fr; }
  .controls { position: static; }
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 620px) {
  .game-wrap { padding: 0.55rem; }
  .charts { grid-template-columns: 1fr; }
  canvas { height: 250px; }
  .button-row.three { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}