/* shared.css — presentation chrome for the fan-curve demos (dark, screen-share friendly) */

:root {
  color-scheme: dark;
  --page:        #0d0d0d;
  --surface:     #1a1a19;
  --surface-2:   #222221;
  --ink:         #ffffff;
  --ink-2:       #c3c2b7;
  --muted:       #898781;
  --grid:        #2c2c2a;
  --baseline:    #383835;
  --border:      rgba(255, 255, 255, 0.10);

  /* categorical series (validated for this surface) */
  --s-fan:    #3987e5;   /* slot 1 blue   — the fan curve / airflow */
  --s-sys:    #d95926;   /* slot 2 orange — the system curve / pressure */
  --s-pow:    #199e70;   /* slot 3 aqua   — power */
  --s-eta:    #c98500;   /* slot 4 yellow — efficiency */

  /* status (reserved) */
  --st-good:     #0ca30c;
  --st-warning:  #fab219;
  --st-serious:  #ec835a;
  --st-critical: #d03b3b;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

body {
  margin: 0;
  background: var(--page);
  color: var(--ink);
  font: 17px/1.55 system-ui, -apple-system, "Segoe UI", sans-serif;
}

.page { max-width: 1480px; margin: 0 auto; padding: 0 28px 64px; }

/* ---- header / nav ---- */
header.site {
  display: flex; align-items: baseline; gap: 26px; flex-wrap: wrap;
  padding: 18px 0 14px; margin-bottom: 20px;
  border-bottom: 1px solid var(--border);
}
header.site .brand { font-size: 19px; font-weight: 650; color: var(--ink); text-decoration: none; }
header.site nav { display: flex; gap: 4px; flex-wrap: wrap; flex: 1; align-items: center; }
header.site nav a {
  color: var(--ink-2); text-decoration: none; font-size: 15px;
  padding: 5px 12px; border-radius: 999px;
}
header.site nav a:hover { color: var(--ink); background: var(--surface-2); }
header.site nav a[aria-current="page"] { color: var(--ink); background: var(--surface-2); font-weight: 600; }
header.site nav a.config { margin-left: auto; font-size: 19px; padding: 4px 11px; }

h1 { font-size: 30px; line-height: 1.2; margin: 6px 0 4px; letter-spacing: -0.015em; }

/* ---- collapsible page title (h1 + hidden lede) ---- */
details.fold { margin: 0 0 20px; }
details.fold > summary {
  list-style: none; cursor: pointer;
  display: inline-flex; align-items: baseline; gap: 13px;
}
details.fold > summary::-webkit-details-marker { display: none; }
details.fold > summary h1 { margin: 6px 0 2px; }
details.fold > summary::after {
  content: '▸'; font-size: 23px; color: var(--muted);
  position: relative; top: -2px;
}
details.fold > summary:hover::after { color: var(--ink); }
details.fold[open] > summary::after { content: '▾'; }
details.fold .lede { margin: 8px 0 2px; }

/* ---- collapsible card section (summary styled as the card heading) ---- */
details.sub > summary {
  list-style: none; cursor: pointer;
  display: flex; align-items: center; gap: 10px;
  font-size: 17px; font-weight: 600;
}
details.sub > summary::-webkit-details-marker { display: none; }
details.sub > summary::before { content: '▸'; color: var(--muted); font-size: 15px; }
details.sub > summary:hover::before { color: var(--ink); }
details.sub[open] > summary::before { content: '▾'; }
details.sub[open] > summary { margin-bottom: 8px; }
h2 { font-size: 21px; margin: 0 0 10px; letter-spacing: -0.01em; }
h3 { font-size: 17px; margin: 0 0 8px; }
p.lede { color: var(--ink-2); font-size: 18px; max-width: 72ch; margin: 0 0 22px; }
a { color: var(--s-fan); }

/* ---- layout ---- */
.layout { display: grid; grid-template-columns: 320px 1fr; gap: 22px; align-items: start; }
.layout.wide-side { grid-template-columns: 380px 1fr; }
@media (max-width: 1000px) { .layout, .layout.wide-side { grid-template-columns: 1fr; } }
.stack { display: grid; gap: 18px; }
.row { display: flex; gap: 18px; flex-wrap: wrap; align-items: stretch; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 18px 20px;
}
.card > h2:first-child, .card > h3:first-child { margin-top: 2px; }

/* ---- stat tiles ---- */
.stats { display: flex; gap: 14px; flex-wrap: wrap; margin: 0 0 18px; }
.stat {
  background: var(--surface); border: 1px solid var(--border); border-radius: 14px;
  padding: 12px 20px 14px; min-width: 148px; flex: 1;
}
.stat .label { font-size: 13.5px; color: var(--muted); letter-spacing: 0.01em; }
.stat .value { font-size: 36px; font-weight: 600; line-height: 1.15; margin-top: 2px; }
.stat .value small { font-size: 17px; font-weight: 500; color: var(--ink-2); margin-left: 3px; }
.stat.hero .value { font-size: 48px; }
.stat .delta { font-size: 14px; margin-top: 2px; color: var(--ink-2); }
.stat .delta.good { color: var(--st-good); }
.stat[data-accent] { border-top: 3px solid var(--accent, var(--border)); }

/* ---- controls ---- */
.control { margin: 14px 0; }
.control label { display: flex; justify-content: space-between; align-items: baseline; font-size: 15px; color: var(--ink-2); margin-bottom: 6px; }
.control label output { font-size: 17px; font-weight: 650; color: var(--ink); font-variant-numeric: tabular-nums; }
input[type="range"] { width: 100%; height: 28px; accent-color: var(--s-fan); cursor: pointer; }
input[type="range"].sys { accent-color: var(--s-sys); }

input[type="number"], select {
  background: var(--surface-2); color: var(--ink);
  border: 1px solid var(--border); border-radius: 8px;
  font: inherit; padding: 7px 10px; width: 110px;
}
select { width: auto; }

.btn {
  background: var(--surface-2); color: var(--ink);
  border: 1px solid var(--border); border-radius: 10px;
  font: inherit; font-size: 15px; font-weight: 550;
  padding: 9px 14px; cursor: pointer;
}
.btn:hover { border-color: rgba(255,255,255,0.25); }
.btn.primary { background: var(--s-fan); border-color: transparent; color: #fff; }
.btn.primary:hover { filter: brightness(1.1); }
.btn:disabled { opacity: 0.45; cursor: default; }
.btn-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 10px; }

.layers { display: grid; gap: 4px; }
.layers label {
  display: flex; align-items: center; gap: 10px;
  font-size: 15.5px; color: var(--ink-2);
  padding: 6px 8px; border-radius: 8px; cursor: pointer;
}
.layers label:hover { background: var(--surface-2); color: var(--ink); }
.layers input { width: 17px; height: 17px; accent-color: var(--s-fan); }
.layers .swatch { width: 20px; height: 4px; border-radius: 2px; flex: none; }

.badge {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 13.5px; font-weight: 600; border-radius: 999px; padding: 3px 11px;
}
.badge.danger  { background: color-mix(in srgb, var(--st-critical) 22%, transparent); color: #ff9d9d; }
.badge.good    { background: color-mix(in srgb, var(--st-good) 20%, transparent); color: #7fd97f; }
.badge.warning { background: color-mix(in srgb, var(--st-warning) 18%, transparent); color: var(--st-warning); }

/* ---- chart chrome ---- */
.chart-wrap { position: relative; }
.chart { display: block; width: 100%; height: auto; border-radius: 10px; outline: none; }
.chart:focus-visible { box-shadow: 0 0 0 2px var(--s-fan); }

.gridline  { stroke: var(--grid); stroke-width: 1; }
.axisline  { stroke: var(--baseline); stroke-width: 1; }
.tick-label { fill: var(--muted); font-size: 13px; font-variant-numeric: tabular-nums; }
.axis-label { fill: var(--ink-2); font-size: 14.5px; }
.direct-label {
  fill: var(--ink); font-size: 14.5px; font-weight: 600;
  paint-order: stroke; stroke: var(--surface); stroke-width: 4px; stroke-linejoin: round;
}
.direct-label.muted { fill: var(--ink-2); font-weight: 500; font-size: 13.5px; }
.crossline { stroke: var(--ink-2); stroke-width: 1; opacity: 0.7; }

.chart-legend { display: flex; gap: 20px; flex-wrap: wrap; padding: 2px 4px 10px; font-size: 14.5px; color: var(--ink-2); }
.legend-item { display: inline-flex; align-items: center; gap: 8px; }
.legend-key { width: 26px; height: 10px; }

.chart-tip {
  position: absolute; z-index: 5; pointer-events: none;
  background: var(--surface-2); border: 1px solid var(--border);
  border-radius: 10px; padding: 9px 12px; min-width: 150px;
  box-shadow: 0 6px 24px rgba(0,0,0,0.45);
  font-size: 14px;
}
.chart-tip .tip-head { color: var(--muted); font-size: 13px; margin-bottom: 5px; font-variant-numeric: tabular-nums; }
.chart-tip .tip-row { display: flex; align-items: center; gap: 8px; padding: 1.5px 0; }
.chart-tip .tip-row strong { font-variant-numeric: tabular-nums; font-weight: 650; }
.chart-tip .tip-row span { color: var(--ink-2); }
.tip-key { width: 20px; height: 8px; flex: none; }

.table-view { margin-top: 10px; font-size: 14.5px; }
.table-view summary { color: var(--muted); cursor: pointer; }
.table-view summary:hover { color: var(--ink-2); }
.table-view table { border-collapse: collapse; margin-top: 8px; }
.table-view th, .table-view td {
  text-align: right; padding: 4px 14px; font-variant-numeric: tabular-nums;
  border-bottom: 1px solid var(--grid);
}
.table-view th { color: var(--muted); font-weight: 600; }
.table-view td:first-child, .table-view th:first-child { text-align: left; }

/* ---- content bits ---- */
.takeaway { border-left: 3px solid var(--s-fan); padding: 2px 0 2px 16px; margin: 14px 0; color: var(--ink-2); }
.takeaway strong { color: var(--ink); }

.eq {
  font-size: 22px; text-align: center; padding: 10px 6px;
  font-variant-numeric: tabular-nums; letter-spacing: 0.01em;
}
.eq sub, .eq sup { font-size: 62%; }
.eq .frac { display: inline-flex; flex-direction: column; vertical-align: middle; margin: 0 4px; }
.eq .frac > span { padding: 0 6px; }
.eq .frac > span:first-child { border-bottom: 1.5px solid var(--ink-2); }

kbd {
  background: var(--surface-2); border: 1px solid var(--border); border-bottom-width: 2px;
  border-radius: 6px; padding: 1px 7px; font-size: 13.5px; font-family: inherit;
}

.note { color: var(--muted); font-size: 14px; }
ul.tight { margin: 8px 0; padding-left: 22px; }
ul.tight li { margin: 5px 0; color: var(--ink-2); }
ul.tight li strong { color: var(--ink); }

canvas.scene { display: block; width: 100%; height: auto; border-radius: 12px; background: var(--surface); }