:root {
  color-scheme: dark;
  --bg: #111827;
  --panel: #182235;
  --panel-2: #202d45;
  --ink: #f4eadc;
  --muted: #b7c2d3;
  --line: #40506c;
  --accent: #f0b35b;
  --bad: #ff8070;
  --good: #9be4b3;
  --water: #294e69;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at 20% 0%, #263554 0, transparent 34rem), var(--bg);
  color: var(--ink);
  font: 16px/1.5 system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
.shell { width: min(1120px, calc(100% - 32px)); margin: 0 auto; padding: 36px 0 56px; }
.hero { margin-bottom: 22px; }
.eyebrow { color: var(--accent); text-transform: uppercase; letter-spacing: .12em; font-size: .78rem; font-weight: 800; }
h1 { font-size: clamp(2.6rem, 8vw, 6rem); line-height: .9; margin: 0 0 12px; }
h2, h3 { margin-top: 0; }
.lede { max-width: 760px; font-size: 1.2rem; color: var(--muted); }
.disclosure { display: inline-block; border: 1px solid var(--line); background: #101725; color: var(--muted); padding: 8px 12px; border-radius: 999px; }
.card { background: linear-gradient(180deg, rgba(255,255,255,.04), transparent), var(--panel); border: 1px solid var(--line); border-radius: 18px; padding: 20px; box-shadow: 0 18px 60px rgba(0,0,0,.25); }
.world { margin-bottom: 18px; }
.world p { max-width: 860px; }
.play-grid { display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(280px, .65fr); gap: 18px; margin-bottom: 18px; }
.hint { color: var(--muted); }
label { display: block; font-weight: 800; margin-bottom: 8px; }
textarea { width: 100%; min-height: 190px; resize: vertical; border-radius: 14px; border: 1px solid var(--line); padding: 14px; background: #0d1421; color: var(--ink); font: 1rem/1.45 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
.button-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 12px; }
button { border: 0; border-radius: 999px; padding: 11px 16px; background: var(--accent); color: #1c1206; font-weight: 900; cursor: pointer; }
button.secondary { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.parse-panel { margin-top: 14px; border: 1px solid var(--line); border-radius: 14px; padding: 12px; background: #101725; }
.parse-panel h3 { margin-bottom: 8px; font-size: .95rem; }
.parse-panel dl { display: grid; grid-template-columns: 6.5rem 1fr; gap: 6px 10px; margin: 0; }
.parse-panel dt { color: var(--accent); font-weight: 900; }
.parse-panel dd { margin: 0; color: var(--muted); }
.syntax ol { padding-left: 20px; color: var(--muted); }
code { color: var(--good); }
.run-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
#status { color: var(--accent); font-weight: 800; }
.map { display: grid; grid-template-columns: repeat(6, minmax(70px, 1fr)); gap: 8px; margin: 12px 0 18px; }
.cell { min-height: 74px; border: 1px solid var(--line); border-radius: 12px; padding: 8px; background: var(--panel-2); color: var(--muted); position: relative; }
.cell.water { background: linear-gradient(135deg, var(--water), #1b3046); }
.cell.active { outline: 3px solid var(--accent); color: var(--ink); }
.cell .name { display: block; font-weight: 900; color: var(--ink); }
.cell .tags { font-size: .8rem; }
.log { padding-left: 24px; }
.log li { margin: 8px 0; color: var(--muted); }
.log strong { color: var(--ink); }
.log .break { color: var(--bad); font-weight: 900; }
.proof { margin-top: 18px; }
.hidden { display: none; }
.proof-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
pre { white-space: pre-wrap; background: #0d1421; border: 1px solid var(--line); border-radius: 14px; padding: 12px; color: var(--ink); }
.failure { color: var(--bad); font-weight: 900; }
.copy-status { min-height: 1.4em; color: var(--good); }
@media (max-width: 820px) {
  .play-grid, .proof-grid { grid-template-columns: 1fr; }
  .map { grid-template-columns: repeat(2, 1fr); }
}