:root {
  --canvas: #0b0c0d;
  --panel: #121314;
  --heading: #f4f5f6;
  --body: #c5c8ce;
  --muted: #8d919a;
  --faint: #6a6e76;
  --edge: rgba(255, 255, 255, 0.12);
  --rule: rgba(255, 255, 255, 0.16);
  --action: #e6e6e8;
  --ink: #121314;
  --proof: #e6e7ea;
  --signal: #3c9a62;
  --warn: #f0c7c7;
  --sans: "IBM Plex Sans", "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;
  color-scheme: dark;
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--canvas); color: var(--heading); }
body { font: 400 15px/1.6 var(--sans); letter-spacing: -0.011em; }
a { color: inherit; }
button, input, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
:focus-visible { outline: 2px solid var(--action); outline-offset: 3px; }
.wrap { width: min(1180px, calc(100% - 48px)); margin: 0 auto; }
.top { display: flex; flex-wrap: wrap; align-items: center; gap: 18px 28px; min-height: 64px; border-bottom: 1px solid var(--rule); padding: 10px 0; }
.mark { font-weight: 500; letter-spacing: -0.022em; text-decoration: none; }
.mark span { color: var(--muted); font-weight: 400; }
nav { display: flex; gap: 18px; }
nav a { color: var(--muted); text-decoration: none; font-size: 13px; }
nav a[aria-current="page"] { color: var(--heading); }
.grow { margin-left: auto; display: flex; align-items: center; gap: 16px; }
.switcher { position: relative; }
.switcher summary { list-style: none; min-height: 44px; display: flex; align-items: center; gap: 8px; cursor: pointer; }
.switcher summary::-webkit-details-marker { display: none; }
.switcher summary small { color: var(--faint); font: 400 11px/1 var(--mono); letter-spacing: 0.04em; text-transform: uppercase; }
.menu { position: absolute; z-index: 2; top: calc(100% + 8px); left: 0; width: 280px; background: var(--panel); border: 1px solid var(--edge); border-radius: 12px; padding: 14px 16px; }
.menu strong { display: block; font-weight: 500; }
.menu p { margin: 8px 0 0; color: var(--muted); font-size: 13px; }
.signal { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 13px; }
.signal i { width: 8px; height: 8px; border-radius: 50%; background: var(--signal); display: block; }
.ghost { background: transparent; border: 0; color: var(--muted); min-height: 44px; padding: 0 4px; }
h1 { margin: 0; font-weight: 500; font-size: clamp(40px, 5vw, 64px); line-height: 1; letter-spacing: -0.022em; text-wrap: balance; }
.lead { max-width: 38rem; color: var(--body); margin: 16px 0 0; }
.stage { padding: 72px 0 96px; }
.split { display: grid; grid-template-columns: 1fr 1fr 1fr; margin-top: 28px; border-top: 1px solid var(--rule); }
.split a { display: block; min-height: 220px; padding: 28px 28px 32px; text-decoration: none; }
.split a + a { border-left: 1px solid var(--rule); }
.split a:hover { background: rgba(255, 255, 255, 0.03); }
.split small { display: block; margin-bottom: 28px; color: var(--faint); font: 400 12px/1.4 var(--mono); text-transform: uppercase; }
.split strong { display: block; font-size: 32px; font-weight: 500; letter-spacing: -0.022em; }
.split span { display: block; margin-top: 12px; color: var(--muted); max-width: 28rem; }
.proof { margin-top: 28px; background: var(--proof); color: var(--ink); border-radius: 8px; padding: 24px 32px; max-width: 640px; }
.proof p { margin: 0; font-size: 20px; line-height: 1.35; letter-spacing: -0.012em; }
.gate { max-width: 420px; margin-top: 48px; }
label { display: block; margin-bottom: 8px; color: var(--muted); font-size: 13px; }
input[type="password"], input[type="text"], input:not([type]), input[type="file"], textarea {
  width: 100%; background: var(--panel); border: 1px solid var(--edge); border-radius: 12px; padding: 12px 14px;
}
textarea { min-height: 140px; resize: vertical; }
.pill { min-height: 44px; padding: 0 20px; border: 0; border-radius: 999px; background: var(--action); color: var(--ink); font-weight: 500; }
.pill:disabled { opacity: 0.45; cursor: default; }
.pill:active { transform: scale(0.97); }
.err { color: var(--warn); min-height: 1.4em; }
.trio, .board { display: grid; border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); margin-top: 36px; }
.trio { grid-template-columns: repeat(3, 1fr); }
.board { grid-template-columns: repeat(6, 1fr); }
.trio a, .trio div, .board div { min-height: 148px; padding: 22px 18px 26px; text-decoration: none; color: inherit; }
.trio a + a, .trio div + div { border-left: 1px solid var(--rule); }
.trio b { display: block; margin-top: 18px; font-weight: 400; font-size: 48px; letter-spacing: -0.03em; line-height: 1; }
.board div + div { border-left: 1px solid var(--rule); }
.board b { display: block; margin-top: 28px; font-weight: 400; font-size: 48px; letter-spacing: -0.03em; line-height: 1; }
.board span, .pair span, table th { color: var(--faint); font: 400 11px/1.35 var(--mono); letter-spacing: 0.04em; text-transform: uppercase; }
.pair { display: grid; grid-template-columns: 1fr 1fr; margin-top: 36px; }
.pair div { padding: 8px 0 20px; }
.pair div + div { padding-left: 28px; border-left: 1px solid var(--rule); }
.pair b { display: block; margin-top: 8px; font-weight: 400; font-size: 32px; letter-spacing: -0.03em; }
.filters { display: flex; gap: 8px; margin-top: 36px; }
.filters button { min-height: 36px; padding: 0 12px; border-radius: 999px; border: 1px solid var(--edge); background: transparent; color: var(--muted); }
.filters button[aria-pressed="true"] { background: var(--action); color: var(--ink); border-color: var(--action); }
table { width: 100%; border-collapse: collapse; margin-top: 12px; }
th, td { text-align: left; padding: 14px 12px 14px 0; border-bottom: 1px solid var(--rule); vertical-align: top; }
td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }
td.msg { max-width: 280px; color: var(--body); }
.when { color: var(--muted); font: 400 12px/1.4 var(--mono); }
.steps { margin-top: 40px; }
.step { display: grid; grid-template-columns: 120px 1fr; gap: 24px; padding: 28px 0; border-top: 1px solid var(--rule); }
.step small { color: var(--faint); font: 400 12px/1.4 var(--mono); text-transform: uppercase; }
.row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; margin-top: 14px; }
.note { color: var(--muted); }
dialog { width: min(480px, calc(100% - 32px)); background: var(--panel); color: var(--heading); border: 1px solid var(--edge); border-radius: 12px; padding: 24px; }
dialog::backdrop { background: rgba(0, 0, 0, 0.62); }
dialog h2 { margin: 0 0 8px; font-size: 24px; font-weight: 500; letter-spacing: -0.02em; }
dialog p { color: var(--body); margin: 0 0 18px; }
.visit { border-top: 1px solid var(--rule); padding: 18px 0; }
.visit button { background: transparent; border: 0; color: var(--heading); padding: 0; min-height: 44px; text-align: left; }
.typed { display: grid; grid-template-columns: 140px 1fr; gap: 8px 16px; margin: 18px 0 28px; }
.typed span { color: var(--faint); font: 400 11px/1.35 var(--mono); letter-spacing: 0.04em; text-transform: uppercase; }
ol.lines { margin: 0; padding: 0; list-style: none; }
tr.pick { cursor: pointer; }
tr.pick.chosen { background: rgba(255, 255, 255, 0.05); }
pre.log { white-space: pre-wrap; font: 400 12px/1.45 var(--mono); background: var(--panel); border: 1px solid var(--edge); border-radius: 12px; padding: 14px; overflow: auto; }
ol.lines li { display: grid; grid-template-columns: 64px 1fr; gap: 12px; padding: 8px 0; border-top: 1px solid var(--rule); color: var(--body); }
ol.lines time { color: var(--faint); font: 400 12px/1.4 var(--mono); }
@media (max-width: 800px) {
  .wrap { width: min(1180px, calc(100% - 32px)); }
  .split, .board, .trio, .step { grid-template-columns: 1fr; }
  .split a + a, .board div + div, .trio a + a, .trio div + div { border-left: 0; border-top: 1px solid var(--rule); }
  .pair { grid-template-columns: 1fr 1fr; }
  .grow { margin-left: 0; width: 100%; }
  h1 { font-size: 40px; }
  .board b { font-size: 40px; }
  table { display: block; overflow-x: auto; }
}