:root {
  --fg: #1f2328;
  --muted: #57606a;
  --bg: #ffffff;
  --border: #d0d7de;
  --accent: #0969da;
  --main: #d1242f;
  --reference: #1f883d;
  --citation: #8250df;
  --expanded: #9198a1;
}
@media (prefers-color-scheme: dark) {
  :root {
    --fg: #e6edf3;
    --muted: #9198a1;
    --bg: #0d1117;
    --border: #30363d;
    --accent: #4493f8;
  }
}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  display: flex;
  flex-direction: column;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  color: var(--fg);
  background: var(--bg);
}

header {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border);
}
header h1 { font-size: 1.1rem; margin: 0 0 0.5rem; }
#search-form { display: flex; gap: 0.5rem; align-items: center; flex-wrap: wrap; }
#title { flex: 1; min-width: 260px; padding: 0.45rem 0.6rem; font-size: 0.95rem;
  border: 1px solid var(--border); border-radius: 6px; background: var(--bg); color: var(--fg); }
#limit { width: 4rem; padding: 0.4rem; border: 1px solid var(--border); border-radius: 6px;
  background: var(--bg); color: var(--fg); }
label { font-size: 0.85rem; color: var(--muted); display: flex; gap: 0.35rem; align-items: center; }
button { padding: 0.45rem 0.9rem; font-size: 0.9rem; border: 1px solid var(--accent);
  background: var(--accent); color: #fff; border-radius: 6px; cursor: pointer; }
button:disabled { opacity: 0.6; cursor: progress; }
button.secondary { background: var(--bg); color: var(--accent); }

#view-controls { display: flex; gap: 0.9rem; align-items: center; flex-wrap: wrap;
  margin-top: 0.5rem; font-size: 0.85rem; }
#view-controls label.check { cursor: pointer; }
#view-controls select, #view-controls input[type="number"] {
  padding: 0.3rem 0.4rem; border: 1px solid var(--border); border-radius: 6px;
  background: var(--bg); color: var(--fg); font-size: 0.85rem; }
#view-controls input[type="number"] { width: 4.5rem; }

#view-controls .control-sep { width: 1px; align-self: stretch; background: var(--border); }
#view-controls .hint { font-size: 0.78rem; color: var(--muted); font-style: italic; }

.status { margin-top: 0.5rem; font-size: 0.85rem; min-height: 1.1rem; color: var(--muted); }
.status.error { color: var(--main); }

main { position: relative; flex: 1; min-height: 0; }
#cy { position: absolute; inset: 0; }

.panel {
  position: absolute; top: 1rem; right: 1rem; width: 320px; max-width: calc(100% - 2rem);
  padding: 1rem 1.1rem; background: var(--bg); border: 1px solid var(--border);
  border-radius: 10px; box-shadow: 0 6px 24px rgba(0,0,0,0.18);
}
.panel.hidden { display: none; }
.panel h2 { font-size: 1rem; margin: 0 1.5rem 0.5rem 0; line-height: 1.3; }
.panel .muted { color: var(--muted); font-size: 0.85rem; margin: 0.25rem 0; }
.panel a { color: var(--accent); font-size: 0.9rem; }
.panel-close { position: absolute; top: 0.4rem; right: 0.5rem; background: none; border: none;
  color: var(--muted); font-size: 1.3rem; line-height: 1; padding: 0; width: auto; }
#expand-btn { margin-top: 0.6rem; width: 100%; }

footer { padding: 0.5rem 1rem; border-top: 1px solid var(--border);
  display: flex; gap: 1.2rem; flex-wrap: wrap; font-size: 0.8rem; color: var(--muted); }
.legend { display: inline-flex; align-items: center; gap: 0.35rem; }
.dot { width: 0.7rem; height: 0.7rem; border-radius: 50%; display: inline-block; }
.dot.main { background: var(--main); }
.dot.reference { background: var(--reference); }
.dot.citation { background: var(--citation); }
.dot.expanded { background: var(--expanded); }

/* Per-expansion legend rows are appended here at runtime. display:contents
   lets each row sit directly in the footer's flex flow (inheriting its gap). */
.expansion-legend { display: contents; }
.legend.expansion { gap: 0.3rem; }
.legend.expansion b { font-weight: 600; color: var(--fg); margin-right: 0.1rem; }
.legend.expansion .collapse-x {
  margin-left: 0.15rem; padding: 0 0.3rem; font-size: 0.9rem; line-height: 1.2;
  border: 1px solid var(--border); background: var(--bg); color: var(--muted); border-radius: 4px;
}
.legend.expansion .collapse-x:hover { color: var(--main); border-color: var(--main); }
/* A collapsed expansion's row is greyed out; "Show all" restores it. */
.legend.expansion.collapsed { opacity: 0.45; }
.legend.expansion.collapsed b { text-decoration: line-through; }