:root {
  --bg: #fbfaf8; --fg: #171614; --muted: #6b675f; --line: #e4e0d8;
  --card: #ffffff; --accent: #b45309; --accent2: #0f766e; --code: #f3efe7;
  --bad: #b91c1c; --good: #15803d; --hero: linear-gradient(160deg, #fef3c7 0%, #fbfaf8 70%);
  --c-prompt: #2563eb; --c-model: #b45309; --c-judge: #7c3aed;
  --c-mem: #0f766e; --c-exec: #64748b;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12110f; --fg: #ece8e1; --muted: #a29c90; --line: #2c2a26;
    --card: #1a1815; --accent: #fbbf24; --accent2: #5eead4; --code: #22201c;
    --bad: #f87171; --good: #4ade80; --hero: linear-gradient(160deg, #2a2113 0%, #12110f 70%);
    --c-prompt: #60a5fa; --c-model: #fbbf24; --c-judge: #c084fc;
    --c-mem: #5eead4; --c-exec: #94a3b8;
  }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--fg);
  font: 17px/1.65 ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif; }
.wrap { max-width: 920px; margin: 0 auto; padding: 0 24px; }

.hero { background: var(--hero); border-bottom: 1px solid var(--line); padding: 56px 0 34px; }
.eyebrow { color: var(--accent); font-size: 13px; font-weight: 700;
  letter-spacing: .12em; text-transform: uppercase; }
.eyebrow a { color: inherit; text-decoration: none;
  border-bottom: 1px dotted color-mix(in srgb, var(--accent) 55%, transparent); }
.eyebrow a:hover { border-bottom-style: solid; }
.hero h1 { font-size: clamp(2.1rem, 5vw, 3.2rem); line-height: 1.08;
  letter-spacing: -.03em; margin: .3em 0 .2em; }
.lede { font-size: 1.16rem; max-width: 48ch; color: var(--muted); margin: 0; }
.meta { font-size: .84rem; color: var(--muted); margin-top: 1.1rem; }
.meta .dot { display: inline-block; width: .55em; height: .55em; background: var(--good);
  border-radius: 50%; margin-right: .45em; vertical-align: .06em; }
.flow { display: flex; align-items: center; gap: 5px; margin-top: 20px;
  flex-wrap: wrap; font-size: .74rem; }
.flow .node { border: 1px solid var(--line); background: var(--card); border-radius: 7px;
  padding: 5px 8px; font-family: ui-monospace, monospace; color: var(--muted);
  transition: border-color .3s, color .3s, box-shadow .3s; }
.flow .node[data-flow-node="memory"] { color: var(--c-mem); }
.flow .node[data-flow-node="prompt"] { color: var(--c-prompt); }
.flow .node[data-flow-node="35b"],
.flow .node[data-flow-node="27b"] { color: var(--c-model); }
.flow .node[data-flow-node="judge"] { color: var(--c-judge); }
.flow .node[data-flow-node="verify"],
.flow .node[data-flow-node="answer"] { color: var(--good); }
.flow .node.api { color: var(--c-exec); opacity: .55; }
.flow .node.active { border-color: var(--packet, var(--accent));
  color: var(--packet, var(--accent));
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--packet, var(--accent)) 18%, transparent); }
.flow .link { flex: 1 1 22px; min-width: 16px; height: 2px; background: var(--line);
  position: relative; overflow: hidden; }
.flow .link.dashed { background: none; border-top: 2px dashed var(--line); height: 0; }
.flow .link i { position: absolute; top: -3px; left: -8px; width: 7px; height: 8px;
  border-radius: 4px; background: var(--packet, var(--accent)); opacity: 0; }
.flow .link.dashed i { top: -5px; }
.flow .link.active i { animation: travel 1.15s linear; opacity: 1; }
.flow .link .p { position: absolute; width: 5px; height: 5px; border-radius: 50%;
  opacity: 0; pointer-events: none; }
.flow .link .p.ltr { background: var(--c-mem); top: -5px; }
.flow .link .p.rtl { background: var(--c-prompt); top: 3px; }
.flow .link.exchange { overflow: visible; }
.flow .link.exchange .p.ltr { animation: ex-ltr 1.25s linear infinite; }
.flow .link.exchange .p.rtl { animation: ex-rtl 1.25s linear infinite; }
.flow .link.exchange .p.d1 { animation-delay: .62s; }
@keyframes ex-ltr { 0% { left: -6px; opacity: 0; } 12% { opacity: 1; }
  88% { opacity: 1; } 100% { left: 100%; opacity: 0; } }
@keyframes ex-rtl { 0% { left: 100%; opacity: 0; } 12% { opacity: 1; }
  88% { opacity: 1; } 100% { left: -6px; opacity: 0; } }
@keyframes travel { 0% { left: -8px; opacity: 0; } 15% { opacity: 1; }
  85% { opacity: 1; } 100% { left: 100%; opacity: 0; } }
  88% { opacity: 1; } 100% { left: 100%; opacity: 0; } }

.tabs { position: sticky; top: 0; z-index: 20;
  background: color-mix(in srgb, var(--bg) 90%, transparent);
  backdrop-filter: blur(10px); border-bottom: 1px solid var(--line); }
.tabs .wrap { display: flex; gap: 4px; overflow-x: auto; padding-top: 10px; padding-bottom: 10px; }
.tabs a { padding: .38rem .72rem; border-radius: 999px; color: var(--muted);
  text-decoration: none; font-size: .82rem; white-space: nowrap; }
.tabs a:hover { color: var(--fg); }
.tabs a[aria-selected="true"] { background: var(--accent); color: #fff; }
@media (prefers-color-scheme: dark) { .tabs a[aria-selected="true"] { color: #1a1815; } }

.stage-wrap { padding: 22px 0 6px; }
.stage { background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  padding: 16px 18px 18px; }
.stage-head { font-size: .72rem; text-transform: uppercase; letter-spacing: .09em;
  color: var(--muted); margin-bottom: 10px; }
.stage-head strong { color: var(--accent); font-weight: 700; }
.stage-panel[hidden] { display: none; }
.tab-panel[hidden] { display: none; }
main { padding: 10px 0 24px; }
h2 { font-size: 1.45rem; letter-spacing: -.01em; margin: 2rem 0 .5rem;
  padding-bottom: .3rem; border-bottom: 1px solid var(--line); }
h3 { font-size: 1.08rem; margin: 1.4rem 0 .3rem; }
p { margin: .75rem 0; }
a { color: var(--accent); text-underline-offset: 3px; }
.sub { color: var(--muted); margin-top: -.1rem; }
.small { font-size: .85rem; color: var(--muted); }
table { width: 100%; border-collapse: collapse; margin: .9rem 0 1.2rem;
  font-size: .91rem; display: block; overflow-x: auto; }
th, td { text-align: left; padding: .5rem .65rem; border-bottom: 1px solid var(--line);
  vertical-align: top; }
th { color: var(--muted); font-size: .74rem; text-transform: uppercase;
  letter-spacing: .06em; font-weight: 600; }
code { background: var(--code); padding: .12em .38em; border-radius: 4px;
  font-size: .9em; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }
pre { background: var(--code); padding: 1rem 1.1rem; border-radius: 8px;
  overflow-x: auto; font-size: .85rem; line-height: 1.5; }
pre code { background: none; padding: 0; }
a.ref { text-decoration: none; border-bottom: 1px dotted var(--accent); }
a.ref code { color: inherit; }
blockquote { margin: 1.1rem 0; padding: .1rem 0 .1rem 1rem;
  border-left: 3px solid var(--accent); color: var(--muted); }
hr { border: 0; border-top: 1px solid var(--line); margin: 2.2rem 0; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px; margin: 1rem 0 1.2rem; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 10px;
  padding: 14px 16px 12px; }
.card h3 { margin: 0 0 .25rem; font-size: .95rem; }
.card p { margin: 0; font-size: .87rem; color: var(--muted); }
.note { background: var(--code); border-left: 3px solid var(--accent);
  padding: .75rem .95rem; border-radius: 0 6px 6px 0; font-size: .89rem; }
.note.good { border-left-color: var(--good); }
.pill { display: inline-block; border: 1px solid var(--line); border-radius: 999px;
  padding: .08rem .5rem; font-size: .74rem; color: var(--muted); margin-right: .3rem; }

.lead { font-size: 1.12rem; }
.thesis-q { font-size: 1.4rem; letter-spacing: -.01em; margin: 0 0 .3rem; }
.path { display: flex; gap: 8px; align-items: stretch; flex-wrap: wrap; margin-top: 14px; }
.path button { flex: 1 1 150px; text-align: left; border: 1px solid var(--line);
  border-radius: 9px; padding: 10px 12px; background: var(--bg); cursor: pointer;
  font: inherit; font-size: .9rem; color: var(--fg); }
.path button small { display: block; color: var(--muted); font-size: .74rem;
  margin-top: 2px; }
.path button:hover { border-color: var(--accent); }
.path .arrow { align-self: center; color: var(--muted); }
@media (max-width: 700px) { .path .arrow { display: none; } }
/* stage demos */
.demo-head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; }
.demo-head h3 { margin: 0; }
button { font: inherit; font-size: .78rem; padding: .25rem .65rem; border-radius: 999px;
  border: 1px solid var(--line); background: var(--bg); color: var(--fg); cursor: pointer; }
button:hover { border-color: var(--accent); color: var(--accent); }
.caption { min-height: 2.9em; margin: .7rem 0 0; font-size: .88rem; color: var(--muted); }
.caption strong { color: var(--fg); }
.labflow { margin-top: 6px; }
.flow .node b { font-weight: 700; }
.lab { display: grid; grid-template-columns: 1.1fr .9fr; gap: 18px; margin-top: 12px; }
@media (max-width: 760px) { .lab { grid-template-columns: 1fr; } }
.lab-row { display: grid; grid-template-columns: 44px 1fr 52px 38px 16px; gap: 7px;
  align-items: center; padding: 4px 0; border-bottom: 1px solid var(--line);
  font-size: .8rem; }
.lab-row .lab-text { font-size: .77rem; color: var(--muted); overflow: hidden;
  white-space: nowrap; text-overflow: ellipsis; }
.lab-row.selected .pick { color: var(--good); }
.lab-row .pick { color: var(--muted); text-align: center; }
.lab-row.merge .lab-text { color: var(--bad); text-decoration: line-through; }
@media (max-width: 720px) { .lab-row { grid-template-columns: 40px 1fr 38px 14px; }
  .lab-row .vec { display: none; } }
.query { margin-top: 10px; font-size: .9rem; color: var(--muted); }
.query strong { color: var(--fg); }
.context-box { border: 1px solid var(--line); border-radius: 8px; padding: 7px;
  display: grid; gap: 5px; margin-top: 5px; }
.ctx-item { font-size: .76rem; background: var(--code); border-radius: 5px;
  padding: 5px 7px; transition: color .3s, opacity .3s; }
.ctx-item.lost { color: var(--bad); text-decoration: line-through; opacity: .55; }
.lab-row .lab-name { font-family: ui-monospace, monospace; color: var(--muted); }
.lab-row .cos { text-align: right; font-family: ui-monospace, monospace;
  color: var(--muted); font-size: .74rem; }
.lab-row.merge .lab-name, .lab-row.merge .cos { color: var(--bad); }
.lab-row.dim { opacity: .45; }
.vec { display: flex; gap: 2px; align-items: flex-end; height: 20px; }
.vec i { flex: 1; background: var(--c-mem); border-radius: 2px 2px 0 0;
  opacity: .8; min-height: 1px; }
.lab-decision { min-height: 3em; font-size: .84rem; margin: .6rem 0 0; color: var(--muted); }
.lab-decision strong { color: var(--fg); }
.slider { display: flex; align-items: center; gap: 10px; margin-top: 12px;
  font-size: .82rem; color: var(--muted); }
.slider input { flex: 1; accent-color: var(--accent); }
.slider output { font-family: ui-monospace, monospace; color: var(--fg);
  min-width: 3.2em; text-align: right; }
.chunks { display: grid; gap: 6px; margin-top: 10px; }
.chunk { display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center;
  border: 1px solid var(--line); border-radius: 8px; padding: 8px 10px; font-size: .84rem;
  transition: opacity .4s, border-color .4s; background: var(--bg); }
.chunk .tag { font-size: .68rem; color: var(--muted); font-family: ui-monospace, monospace; }
.chunk.merged { opacity: .28; border-style: dashed; }
.chunk.kept { border-color: var(--good); }
.chunk.dimmed { opacity: .4; border-color: var(--accent); }
.seg { display: inline-flex; border: 1px solid var(--line); border-radius: 999px;
  overflow: hidden; }
.seg button { border: 0; border-radius: 0; padding: .24rem .62rem;
  background: transparent; color: var(--muted); }
.seg button[aria-pressed="true"] { background: var(--accent); color: #fff; }
@media (prefers-color-scheme: dark) { .seg button[aria-pressed="true"] { color: #1a1815; } }
.ledger { display: flex; gap: 5px; flex-wrap: wrap; margin-top: 10px; }
.fact { font-size: .7rem; font-family: ui-monospace, monospace;
  border: 1px solid var(--line); border-radius: 999px; padding: .08rem .48rem;
  color: var(--good); transition: color .3s, border-color .3s, opacity .3s; }
.fact.lost { color: var(--bad); border-color: var(--bad);
  text-decoration: line-through; opacity: .8; }
.budget { height: 8px; background: var(--line); border-radius: 999px; overflow: hidden;
  margin-top: 10px; }
.budget i { display: block; height: 100%; background: var(--accent2); width: 100%;
  transition: width .7s ease; }
.route { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; margin-top: 12px; }
@media (max-width: 760px) { .route { grid-template-columns: 1fr; } }
.station { border: 1px solid var(--line); border-radius: 8px; padding: 8px; min-height: 72px;
  background: var(--bg); transition: border-color .3s, box-shadow .3s; }
.station .name { font-family: ui-monospace, monospace; font-size: .72rem; color: var(--muted); }
.station .val { font-size: .92rem; margin-top: 4px; }
.station.active { border-color: var(--accent);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--accent) 18%, transparent); }
.station.pass { border-color: var(--good); }
.station.fail { border-color: var(--bad); }
.q { font-size: .84rem; color: var(--muted); border-left: 2px solid var(--line);
  padding-left: 9px; margin: 8px 0 0; }
.map { display: grid; gap: 5px; }
.map-row { display: grid; grid-template-columns: 1fr 22px 1fr; align-items: center;
  gap: 8px; padding: 6px 9px; border-radius: 7px; font-size: .85rem;
  transition: background .35s; position: relative; cursor: help; }
.map-row:focus { outline: 1px solid var(--accent); outline-offset: 1px; }
.map-row::after { content: attr(data-tip); position: absolute; left: 0; right: 0;
  top: calc(100% + 5px); background: var(--card); border: 1px solid var(--accent);
  border-radius: 8px; padding: 8px 10px; font-size: .78rem; line-height: 1.45;
  color: var(--fg); opacity: 0; pointer-events: none; transition: opacity .15s;
  z-index: 10; box-shadow: 0 8px 22px rgba(0, 0, 0, .18); }
.map-row:hover::after, .map-row:focus::after, .map-row.show-tip::after { opacity: 1; }
.map-row .arrow { text-align: center; color: var(--muted); }
.map-row.active { background: var(--code); }
.bars { display: grid; gap: 7px; margin-top: 10px; }
.bar-row { display: grid; grid-template-columns: 96px 1fr 58px; gap: 9px;
  align-items: center; font-size: .84rem; }
.bar { height: 9px; background: var(--line); border-radius: 999px; overflow: hidden; }
.bar i { display: block; height: 100%; width: 0; background: var(--accent2);
  border-radius: 999px; transition: width .85s ease; }
.bars.animate .bar i { width: var(--v); }
.bar-val { font-family: ui-monospace, monospace; color: var(--muted); font-size: .78rem; }
.check-code { margin: 8px 0 2px; }
.runs { display: grid; gap: 5px; margin: 9px 0; }
.run { display: flex; justify-content: space-between; gap: 10px; border: 1px solid var(--line);
  border-radius: 7px; padding: 6px 10px; font-size: .83rem; }
.verdict { font-family: ui-monospace, monospace; }
.verdict.pass { color: var(--good); } .verdict.fail { color: var(--bad); }
.outcome { font-size: .86rem; padding: .55rem .75rem; border-radius: 7px; background: var(--code); }
.flowmap { width: 100%; height: auto; display: block; margin: 4px 0 2px; }
.flowmap .edge { fill: none; stroke: var(--line); stroke-width: 2;
  transition: stroke .25s, opacity .25s; }
.flowmap .edge.dashed { stroke-dasharray: 5 5; }
.flowmap .edge.active { stroke-width: 3; }
.flowmap .edge.struck { stroke: var(--bad) !important; opacity: .3; }
.flowmap .node rect { fill: var(--bg); stroke: var(--line); stroke-width: 1.4;
  transition: stroke .25s, stroke-width .25s; }
.flowmap .node text { font: 600 12px ui-monospace, SFMono-Regular, Menlo, monospace;
  text-anchor: middle; fill: var(--fg); }
.flowmap .node .val { font-size: 11px; font-weight: 500; fill: var(--muted);
  opacity: .2; transition: opacity .3s; }
.flowmap .node.revealed .val { opacity: 1; }
.flowmap .node .val.fail { fill: var(--bad); }
.flowmap .node .val.pass { fill: var(--good); }
.flowmap .node.active rect { stroke: var(--accent); stroke-width: 2.4; }
.flowmap .node.hub rect { stroke: var(--accent); stroke-width: 2; }
.flowmap .node .sub { font-size: 10px; font-weight: 500; fill: var(--muted); }
.flowmap .node.fail rect { stroke: var(--bad); }
.flowmap .node.pass rect { stroke: var(--good); }
.flowmap .node[data-node="mem"] text { fill: var(--c-mem); }
.flowmap .node[data-node="prompt"] text { fill: var(--c-prompt); }
.flowmap .node[data-node="35b"] text,
.flowmap .node[data-node="27b"] text { fill: var(--c-model); }
.flowmap .node[data-node="judge"] text { fill: var(--c-judge); }
.flowmap .node[data-node="sandbox"] text { fill: var(--c-exec); }
.legend { display: flex; gap: 12px; flex-wrap: wrap; font-size: .72rem;
  color: var(--muted); margin-top: 4px; }
.legend span { display: inline-flex; align-items: center; gap: 5px; }
.legend i { width: 9px; height: 9px; border-radius: 50%; display: inline-block; }
.timing { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 10px;
  font-size: .76rem; color: var(--muted); }
.timing span { border: 1px solid var(--line); border-radius: 999px;
  padding: 2px 8px; transition: border-color .3s, color .3s; }
.timing b { color: var(--fg); font-weight: 600; }
.timing span.active { border-color: var(--accent); color: var(--accent); }
.timing .total { border-color: var(--accent); color: var(--accent); }
.timing-note { font-size: .78rem; color: var(--muted); margin-top: 6px; }
.paper-card { border-left: 3px solid var(--accent); padding: .1rem 0 .1rem 1rem; }
.paper-actions { display: flex; gap: 8px; flex-wrap: wrap; margin: 1rem 0 1.25rem; }
.cta { display: inline-block; background: var(--accent); color: var(--bg);
  padding: 8px 14px; border-radius: 8px; text-decoration: none;
  font-weight: 600; font-size: .9rem; }
.cta:hover { filter: brightness(1.08); }
.cta.ghost { background: transparent; color: var(--accent);
  border: 1px solid var(--accent); }
.paper-card h3 { margin: 0 0 .3rem; font-size: 1.15rem; }
.paper-card p { color: var(--muted); }
footer { border-top: 1px solid var(--line); padding: 24px 0 44px; color: var(--muted);
  font-size: .85rem; }
footer a { color: inherit; }
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}