/* Śrīyantra Certified Plane Atlas — viewer styles.
   Design: warm/cool duality (Śakti red / Śiva indigo), brass certificate seal,
   monospace for every exact numeric value. Light "technical paper" ground. */

@import url('https://fonts.googleapis.com/css2?family=Spectral:ital,wght@0,400;0,500;0,600;1,400&family=IBM+Plex+Sans:wght@400;500;600&family=IBM+Plex+Mono:wght@400;500&display=swap');

:root {
  --paper:      #F7F6F2;
  --tile:       #FFFFFF;
  --ink:        #16181D;
  --ink-soft:   #4C4F57;
  --ink-faint:  #8B8D87;
  --line:       #DCDAD2;
  --sakti:      #B23A48;   /* downward, warm  */
  --siva:       #2E4374;   /* upward, cool    */
  --brass:      #9A7838;   /* certificate seal */
  --brass-bg:   rgba(154,120,56,.10);
  --focus:      #2E4374;

  --f-display: 'Spectral', Georgia, 'Times New Roman', serif;
  --f-ui:      'IBM Plex Sans', system-ui, -apple-system, sans-serif;
  --f-mono:    'IBM Plex Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  --maxw: 1180px;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--paper); color: var(--ink);
  font-family: var(--f-ui); font-size: 15px; line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--siva); text-decoration: none; }
a:hover { text-decoration: underline; }
a.brass { color: var(--brass); }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; border-radius: 2px; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 28px; }

/* ---- masthead ---- */
.masthead { border-bottom: 1px solid var(--line); }
.masthead .wrap { padding-top: 30px; padding-bottom: 26px; }
.eyebrow {
  font-family: var(--f-mono); font-size: 11.5px; letter-spacing: .14em;
  text-transform: uppercase; color: var(--ink-faint); margin: 0 0 10px;
}
.title {
  font-family: var(--f-display); font-weight: 500; font-size: clamp(28px, 4.4vw, 46px);
  line-height: 1.04; letter-spacing: -.01em; margin: 0; max-width: 18ch;
}
.title em { font-style: italic; color: var(--ink-soft); }
.lede {
  margin: 16px 0 0; max-width: 56ch; color: var(--ink-soft); font-size: 16px;
}
.metarow {
  display: flex; flex-wrap: wrap; gap: 10px 26px; align-items: baseline;
  margin-top: 22px; font-family: var(--f-mono); font-size: 12.5px; color: var(--ink-soft);
}
.metarow .count { color: var(--ink); }
.metarow b { color: var(--sakti); font-weight: 500; }
.tau {
  margin-top: 14px; padding: 11px 14px; border-left: 2px solid var(--brass);
  background: var(--brass-bg); border-radius: 0 4px 4px 0;
  font-size: 12.5px; color: var(--ink-soft); max-width: 70ch;
}
.tau b { color: var(--brass); font-family: var(--f-mono); font-weight: 500; }

/* ---- gallery ---- */
main { padding: 34px 0 64px; }
.gallery-head {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 16px; margin-bottom: 20px;
}
.gallery-head h2 {
  font-family: var(--f-display); font-weight: 500; font-size: 19px; margin: 0;
}
.gallery-head .hint { font-size: 12.5px; color: var(--ink-faint); }

.grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 14px;
}
.card {
  background: var(--tile); border: 1px solid var(--line); border-radius: 5px;
  padding: 12px 12px 10px; cursor: pointer; text-align: left;
  transition: transform .14s ease, box-shadow .14s ease, border-color .14s ease;
}
.card:hover, .card:focus-visible {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px -10px rgba(22,24,29,.28);
  border-color: #c9c6bb;
}
.card .thumb { aspect-ratio: 1; width: 100%; display: block; }
.card .cap {
  display: flex; align-items: baseline; justify-content: space-between;
  margin-top: 8px; font-family: var(--f-mono); font-size: 11.5px; color: var(--ink-faint);
}
.card .cap .id { color: var(--ink); }

/* ---- detail / specimen ---- */
.detail { display: grid; grid-template-columns: 1.4fr 1fr; gap: 34px; align-items: start; }
.back {
  font-family: var(--f-mono); font-size: 12px; letter-spacing: .04em;
  color: var(--ink-soft); display: inline-block; margin-bottom: 18px;
}
.stage {
  background: var(--tile); border: 1px solid var(--line); border-radius: 6px;
  position: relative; overflow: hidden;
}
.stage svg { display: block; width: 100%; height: auto; touch-action: none; cursor: grab; }
.stage svg:active { cursor: grabbing; }
.stage .zoomhint {
  position: absolute; right: 10px; bottom: 9px; font-family: var(--f-mono);
  font-size: 10.5px; color: var(--ink-faint); pointer-events: none;
}

.controls { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.toggle {
  font-family: var(--f-mono); font-size: 12px; color: var(--ink-soft);
  background: var(--tile); border: 1px solid var(--line); border-radius: 4px;
  padding: 6px 11px; cursor: pointer; transition: all .12s ease;
}
.toggle[aria-pressed="true"] { color: var(--ink); border-color: var(--ink-soft); background: #fff; }
.toggle:hover { border-color: var(--ink-faint); }

.specimen h2 {
  font-family: var(--f-display); font-weight: 500; font-size: 22px; margin: 0 0 4px;
}
.specimen .sub { font-family: var(--f-mono); font-size: 12px; color: var(--ink-faint); margin-bottom: 20px; }

.seal {
  display: flex; align-items: center; gap: 10px; padding: 12px 14px;
  border: 1px solid var(--brass); border-radius: 5px; background: var(--brass-bg);
  margin-bottom: 22px;
}
.seal .mark {
  font-family: var(--f-mono); font-size: 18px; color: var(--brass); line-height: 1;
}
.seal .txt { font-size: 12.5px; color: var(--ink-soft); }
.seal .txt b { color: var(--ink); font-weight: 500; }
.seal .txt code { font-family: var(--f-mono); color: var(--brass); }

.field { margin-bottom: 18px; }
.field .k {
  font-family: var(--f-mono); font-size: 10.5px; letter-spacing: .12em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: 6px;
}
.params { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; }
.param {
  border: 1px solid var(--line); border-radius: 4px; padding: 7px 8px; background: var(--tile);
}
.param .name { font-family: var(--f-display); font-style: italic; font-size: 13px; color: var(--ink-soft); }
.param .val { font-family: var(--f-mono); font-size: 12px; color: var(--ink); margin-top: 2px; word-break: break-all; }

.kv { font-family: var(--f-mono); font-size: 12.5px; color: var(--ink-soft); }
.kv .v { color: var(--ink); }
.subsets { display: flex; flex-wrap: wrap; gap: 5px; }
.chip {
  font-family: var(--f-mono); font-size: 11px; color: var(--siva);
  border: 1px solid #cdd4e2; background: #f3f5fa; border-radius: 3px; padding: 2px 6px;
}

.export { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 6px; }
.exp-note { margin: 10px 0 0; font-size: 11.5px; color: var(--ink-faint); max-width: 46ch; }
.btn {
  font-family: var(--f-ui); font-size: 13px; font-weight: 500; cursor: pointer;
  border: 1px solid var(--ink); background: var(--ink); color: #fff;
  border-radius: 4px; padding: 9px 15px; transition: opacity .12s ease;
}
.btn.ghost { background: transparent; color: var(--ink); }
.btn:hover { opacity: .85; }

/* legend duality */
.legend { display: flex; gap: 18px; margin-top: 12px; font-family: var(--f-mono); font-size: 11.5px; }
.legend span { display: inline-flex; align-items: center; gap: 6px; color: var(--ink-soft); }
.legend i { width: 16px; height: 0; border-top: 2px solid; display: inline-block; }
.legend .s i { border-color: var(--sakti); }
.legend .v i { border-color: var(--siva); }

/* ---- svg figure element classes ---- */
.fig-circle { fill: none; stroke: var(--line); stroke-width: 1.1px; vector-effect: non-scaling-stroke; }
.fig-axis   { stroke: #e4e2da; stroke-width: 1px; stroke-dasharray: 5 5; vector-effect: non-scaling-stroke; }
.fig-tri    { fill: none; stroke-width: 1.5px; stroke-linejoin: round; vector-effect: non-scaling-stroke; }
.fig-tri.sakti { stroke: var(--sakti); }
.fig-tri.siva  { stroke: var(--siva); }
.fig-foot   { fill: var(--brass); }
.fig-bindu  { fill: var(--ink); }
.fig-base   { fill: var(--ink-faint); }
.fig-pt     { fill: var(--ink-soft); }
.fig-label  { font-family: var(--f-mono); fill: var(--ink-soft); }

/* gentle fade-in for the detail figure (lines stay solid) */
.stage svg.fade-in { animation: figfade .5s ease; }
@keyframes figfade { from { opacity: 0; } to { opacity: 1; } }

/* ---- constraints panel ---- */
.panel { border: 1px solid var(--line); border-radius: 5px; margin-bottom: 18px; background: var(--tile); }
.panel > summary {
  cursor: pointer; padding: 11px 14px; font-family: var(--f-mono); font-size: 12px;
  letter-spacing: .04em; color: var(--ink); list-style: none;
}
.panel > summary::-webkit-details-marker { display: none; }
.panel > summary::before { content: '\25B8\00a0'; color: var(--ink-faint); }
.panel[open] > summary::before { content: '\25BE\00a0'; }
.panel.sub { margin: 4px 14px 12px; background: var(--paper); }
.panel-intro { margin: 0 14px 10px; font-size: 12.5px; color: var(--ink-soft); }
.panel-intro em { font-family: var(--f-display); font-style: italic; color: var(--ink); }
.clist { padding: 0 14px 12px; display: grid; gap: 8px; }
.panel.sub .clist { padding: 8px 12px 10px; }
.citem { display: grid; grid-template-columns: 38px 1fr; column-gap: 10px; row-gap: 2px; opacity: .45; }
.citem.on { opacity: 1; }
.cnum { grid-row: 1 / 3; font-family: var(--f-mono); font-size: 12px; color: var(--sakti); }
.cform { grid-column: 2; font-family: var(--f-mono); font-size: 11px; color: var(--ink-faint); }
.cdesc { grid-column: 2; font-size: 12.5px; color: var(--ink-soft); }
.citem.on .cdesc { color: var(--ink); }
.cdesc em { font-family: var(--f-mono); font-style: normal; font-size: 10.5px; color: var(--ink-faint); }

/* ---- gallery filter ---- */
.filterbar { margin-bottom: 18px; font-family: var(--f-mono); font-size: 12.5px; color: var(--ink-soft); }
.filterbar select {
  font-family: var(--f-mono); font-size: 12.5px; padding: 6px 8px; margin-left: 8px;
  border: 1px solid var(--line); border-radius: 4px; background: var(--tile); color: var(--ink);
}

/* ---- footer ---- */
footer { border-top: 1px solid var(--line); margin-top: 30px; }
footer .wrap { padding: 26px 28px 40px; display: grid; gap: 8px; }
footer p { margin: 0; font-size: 12.5px; color: var(--ink-soft); max-width: 78ch; }
footer .cite { font-family: var(--f-mono); font-size: 12px; color: var(--ink-faint); }
footer .cite a { color: var(--brass); }

.preview-banner {
  background: var(--siva); color: #fff; font-family: var(--f-mono); font-size: 12px;
  text-align: center; padding: 7px 14px;
}

/* ---- responsive ---- */
@media (max-width: 820px) {
  .detail { grid-template-columns: 1fr; gap: 22px; }
  .grid { grid-template-columns: repeat(auto-fill, minmax(132px, 1fr)); }
}
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}

/* ---- reference-figure hero (v1.0.1) ---- */
.hero { display: flex; align-items: center; gap: 18px; margin: 18px 0 0; padding: 12px 14px;
  border: 1px solid var(--line); border-radius: 6px; background: var(--tile); max-width: 640px; }
.hero-img { flex: 0 0 150px; }
.hero-svg { width: 150px; height: 150px; display: block; }
.hero figcaption { font-size: 12.5px; color: var(--ink-soft); }
.hero figcaption b { color: var(--sakti); }