/* Query Engine — retrieval workzone diagrams.
   The KS↔QE boundary drawn three ways: the two-column hand-off (rt-bound — KS
   retrieval vs QE RAG, with a seam carrying the request down and candidates
   up), the identity input chain (rt-flow — QE passes identity, KS resolves and
   pre-filters, candidates rise as the RAG input), and the late-binding trim
   strip (rt-trim — pre-filter → rerank → live-check, narrowing to top-N). All
   sections land on .section (its :target flash lives in module.css), so these
   blocks add none of their own.
   Static — no hover affordance (README §Hover).
   Loaded by _workzone/retrieval.html on top of ../../module.css
   + ../query-engine.css.
   Placement convention: docs/architecture/README.md §Styling. */

/* ════════════════ BOUNDARY HAND-OFF ════════════════ KS retrieval ▾ seam ▴ QE
   RAG — two columns either side of a vertical seam: one query down, candidates
   up. */
.rt-bound {
  display: flex;
  gap: 0.75rem;
  margin: 1rem 0 0.4rem;
}
.rt-bound__col {
  flex: 1;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
}
.rt-bound__col--ks {
  border-left: 4px solid var(--accent);
  background: var(--tint-6);
}
.rt-bound__col--qe {
  border-left: 4px solid var(--s4);
}
.rt-bound__head {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}
.rt-bound__who {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text);
}
.rt-bound__act {
  font-family: var(--mono);
  font-size: 0.6rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}
.rt-bound__col--ks .rt-bound__act {
  color: var(--accent);
}
.rt-bound__col--qe .rt-bound__act {
  color: var(--s4);
}
.rt-bound__list {
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 0.78rem;
  color: var(--text-dim);
  line-height: 1.5;
}
.rt-bound__list li {
  position: relative;
  padding-left: 0.95rem;
  margin-bottom: 0.3rem;
}
.rt-bound__list li::before {
  content: "·";
  position: absolute;
  left: 0.2rem;
  color: var(--accent);
  font-weight: 700;
}
.rt-bound__col--qe .rt-bound__list li::before {
  color: var(--s4);
}
/* Seam — the vertical channel between the two columns: query goes down,
   candidates rise back up. */
.rt-bound__seam {
  flex: 0 0 auto;
  align-self: stretch;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--mono);
  font-size: 0.58rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-align: center;
  white-space: nowrap;
}
.rt-bound__seam-down {
  color: var(--s2);
}
.rt-bound__seam-up {
  color: var(--accent);
}

/* ════════════════ IDENTITY INPUT CHAIN ════════════════ QE passes identity ▸
   KS resolves + pre-filters ▸ candidates under rights — the RAG input. */
.rt-flow {
  display: flex;
  align-items: stretch;
  gap: 0.4rem;
  margin: 1rem 0 0.4rem;
}
.rt-flow__node {
  flex: 1 1 0;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  justify-content: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 0.7rem 0.8rem;
}
.rt-flow__node--qe {
  border-top: 3px solid var(--s2);
}
.rt-flow__node--ks {
  border-top: 3px solid var(--accent);
  background: var(--tint-6);
}
.rt-flow__node--out {
  border-top: 3px solid var(--s4);
}
.rt-flow__t {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text);
}
.rt-flow__s {
  font-family: var(--mono);
  font-size: 0.58rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text-muted);
}
.rt-flow__arr {
  flex: 0 0 auto;
  align-self: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
}
.rt-flow__arr-line {
  font-family: var(--mono);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: -0.05em;
  color: var(--accent);
  line-height: 1;
}
.rt-flow__arr-cap {
  font-family: var(--mono);
  font-size: 0.54rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--text-muted);
  text-align: center;
  max-width: 7rem;
  line-height: 1.3;
}

/* ════════════════ LATE-BINDING TRIM ════════════════ pre-filter (whole index)
   ▸ rerank → top-N ▸ live-check at the source — only on the finalists. */
.rt-trim {
  display: flex;
  align-items: stretch;
  gap: 0.4rem;
  margin: 1rem 0 0.4rem;
}
.rt-trim__stage {
  flex: 1 1 0;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 0.7rem 0.85rem;
}
.rt-trim__stage--fast {
  border-left: 4px solid var(--accent);
  background: var(--tint-6);
}
.rt-trim__stage--rank {
  border-left: 4px solid var(--s2);
}
.rt-trim__stage--live {
  border-left: 4px solid var(--s1);
}
.rt-trim__t {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text);
}
.rt-trim__d {
  font-size: 0.74rem;
  color: var(--text-dim);
  line-height: 1.5;
}
.rt-trim__arr {
  flex: 0 0 auto;
  align-self: center;
  font-size: 1rem;
  font-weight: 700;
  color: var(--accent);
}

@media (max-width: 640px) {
  .rt-bound,
  .rt-flow,
  .rt-trim {
    flex-direction: column;
  }
  .rt-bound__seam {
    flex-direction: row;
    justify-content: center;
    gap: 1.5rem;
  }
  .rt-flow__arr {
    transform: rotate(90deg);
    align-self: flex-start;
    margin-left: 1.5rem;
  }
  .rt-trim__arr {
    transform: rotate(90deg);
    align-self: flex-start;
    margin-left: 1.5rem;
  }
}