/* ==========================================================================
   PCA interactive teaching page — widget styles
   Namespaced .pca-* throughout. Consumes design tokens from course-ml.css
   (--paper, --ink, --accent, --crimson, --good, --warn, --accent-soft,
   --line, --serif, --sans, --mono) — no palette is invented here, only a
   small colourblind-safe CATEGORICAL set for group markers (income / region
   / diagnosis), each colour paired with a distinct SVG shape so meaning
   survives greyscale and colour-vision deficiency. Ordered navy, crimson,
   amber, teal, then three extra hues for the seven-way region grouping.

   Adapted from the gate-verified prototype (pca_prototype.html): the SAME
   interaction behaviour, restyled onto the course design system. Rendering
   logic lives in pca-widgets.js; this file is presentation only.
   ========================================================================== */

:root{
  --pca-g1:var(--accent);   /* navy   + circle   */
  --pca-g2:var(--crimson);  /* crimson+ triangle */
  --pca-g3:var(--warn);     /* amber  + square   */
  --pca-g4:#2a7f8f;         /* teal   + diamond  */
  --pca-g5:#5b3f8f;         /* purple + cross    */
  --pca-g6:#3f7d3f;         /* green  + star     */
  --pca-g7:#8a5a2b;         /* brown  + hex      */
  --pca-point:#9e1b30;      /* neutral data-point red, unlabelled scatters */
}

/* ---- figure card: the repeated unit (instruction + SVG + readouts + caption) */
.pca-card{
  border:1px solid var(--line-strong);border-radius:6px;background:#fff;
  padding:1.2rem 1.25rem 1.15rem;margin:1.7rem 0;
  box-shadow:0 1px 0 rgba(26,26,23,.02);
}
.pca-modtag{font-family:var(--mono);font-size:.64rem;letter-spacing:.14em;
  text-transform:uppercase;color:var(--accent);margin:.15rem 0 .9rem}
.pca-modtag .cr{color:var(--crimson)}

/* ---- instruction line ("Drag the line.") ---- */
.pca-instruction{display:flex;align-items:baseline;gap:.55rem;flex-wrap:wrap;
  font-family:var(--sans);font-weight:600;font-size:.98rem;color:var(--ink);
  margin:0 0 .8rem}
.pca-tag{flex:none;font-family:var(--mono);font-size:.62rem;letter-spacing:.1em;
  text-transform:uppercase;color:#fff;background:var(--accent);
  padding:.22rem .55rem;border-radius:999px;display:inline-flex;align-items:center;gap:.32rem}
.pca-tag i{font-size:.66rem}

/* ---- figure mount points ---- */
.pca-fig{min-width:0}
.pca-fig svg{display:block;width:100%;height:auto;max-width:100%}
.pca-fig svg.pca-draggable{touch-action:none;cursor:grab}
.pca-figrow{display:flex;flex-wrap:wrap;gap:1.3rem;align-items:flex-start;min-width:0}
.pca-figrow>.pca-fig{flex:1 1 320px;min-width:0}
.pca-figrow>.pca-side{flex:1 1 200px;min-width:0}

/* ---- live readouts ---- */
.pca-readouts{display:flex;flex-wrap:wrap;gap:.5rem 1.5rem;margin:.7rem 0 .2rem;
  font-family:var(--mono)}
.pca-ro{font-size:.72rem;letter-spacing:.04em;color:var(--ink-faint);
  text-transform:uppercase}
.pca-ro b{display:block;margin-top:.15rem;font-size:1.32rem;line-height:1.1;
  color:var(--accent);font-family:var(--mono);font-weight:600;
  text-transform:none;letter-spacing:0}
.pca-ro.crim b{color:var(--crimson)}

/* ---- caption / source line ---- */
.pca-caption{font-size:.84rem;line-height:1.55;color:var(--ink-soft);margin:.85rem 0 0}
.pca-caption .src{display:block;margin-top:.25rem;font-family:var(--mono);
  font-size:.72rem;color:var(--ink-faint)}

/* ---- controls row ---- */
.pca-controls{display:flex;flex-wrap:wrap;gap:.6rem;align-items:center;margin:.7rem 0}
.pca-controls label{font-family:var(--mono);font-size:.68rem;letter-spacing:.08em;
  text-transform:uppercase;color:var(--ink-faint)}
.pca-controls input[type=range]{accent-color:var(--accent);width:min(260px,60vw)}

/* ---- segmented toggle group ---- */
.pca-seg{display:inline-flex;border:1px solid var(--accent-hair);border-radius:7px;
  overflow:hidden;background:#fff}
.pca-seg button{font-family:var(--sans);font-size:.82rem;font-weight:500;
  border:none;background:transparent;color:var(--accent);padding:.48rem .8rem;
  cursor:pointer;transition:background-color .15s,color .15s}
.pca-seg button+button{border-left:1px solid var(--accent-hair)}
.pca-seg button[aria-pressed="true"]{background:var(--accent);color:#fff}
.pca-seg button:hover:not([aria-pressed="true"]){background:var(--accent-soft)}

/* ---- buttons ---- */
.pca-btn{font-family:var(--sans);font-size:.85rem;font-weight:600;cursor:pointer;
  border:1px solid var(--accent);background:var(--accent);color:#fff;
  padding:.5rem .9rem;border-radius:7px;transition:transform .12s ease,background-color .15s ease}
.pca-btn:hover{background:var(--accent-strong)}
.pca-btn:active{transform:translateY(1px)}
.pca-btn.ghost{background:transparent;color:var(--accent)}
.pca-btn.ghost:hover{background:var(--accent-soft)}
.pca-btn:disabled{opacity:.55;cursor:default;transform:none}
.pca-btn:disabled:hover{background:var(--accent)}

button.pca-btn:focus-visible,.pca-seg button:focus-visible,
.pca-fig [tabindex]:focus-visible{outline:3px solid var(--warn);outline-offset:2px}

/* ---- legend (colour + shape + label) ---- */
.pca-legend{display:flex;flex-wrap:wrap;gap:.4rem 1rem;margin:.7rem 0 0;font-size:.78rem;
  color:var(--ink-soft)}
.pca-legend .li{display:inline-flex;align-items:center;gap:.4rem}
.pca-legend svg{width:15px;height:15px;flex:none}

/* ---- floating tooltip ---- */
.pca-tooltip{position:fixed;pointer-events:none;z-index:60;background:var(--ink);
  color:#fff;font-family:var(--mono);font-size:.72rem;line-height:1.5;
  padding:.4rem .6rem;border-radius:5px;opacity:0;transition:opacity .08s;
  max-width:230px}

/* ---- vocabulary grid (M3) ---- */
.pca-vocab{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));
  gap:.9rem;margin:1rem 0}
.pca-vocab .term{border-left:3px solid var(--accent);padding:.15rem 0 .15rem .9rem}
.pca-vocab .term h4{font-family:var(--serif);font-weight:600;font-size:1rem;
  color:var(--ink);margin:0 0 .25rem;letter-spacing:-.005em}
.pca-vocab .term p{font-size:.88rem;line-height:1.55;color:var(--ink-soft);margin:0}

/* ---- inline formula chip ---- */
.pca-eq{font-family:var(--mono);font-size:.86em;background:var(--accent-soft);
  color:var(--accent-strong);padding:.06em .38em;border-radius:4px}

/* ---- ranked chip strip (M9) ---- */
.pca-rank{display:flex;flex-wrap:wrap;gap:.4rem;margin:.8rem 0}
.pca-chip{font-family:var(--mono);font-size:.72rem;border:1px solid var(--line-strong);
  border-radius:999px;padding:.25rem .65rem;background:#fff;color:var(--ink)}

/* ---- SVG-internal presentation classes (set by pca-widgets.js) ---- */
.pca-axis{stroke:var(--ink-faint);stroke-width:1}
.pca-gridline{stroke:var(--line);stroke-width:1}
.pca-axis-lbl{font-family:var(--mono);font-size:11px;fill:var(--ink-faint)}
.pca-barlabel{font-family:var(--mono);font-size:11px;fill:var(--ink)}

/* ---- reconstruction sparkline sub-caption ---- */
.pca-recon-cap{font-family:var(--mono);font-size:.7rem;color:var(--ink-faint);
  margin:0 0 .4rem}

/* ---- shape-switcher / colour-toggle groups reuse .pca-seg above ---- */

/* ---- responsiveness: figure cards never force body scroll ---- */
@media (max-width:620px){
  .pca-card{padding:1rem 1rem .95rem;margin:1.3rem 0}
  .pca-ro b{font-size:1.15rem}
  .pca-controls input[type=range]{width:min(220px,54vw)}
}

/* ---- reduced motion: snap, do not animate (JS also checks this) ---- */
@media (prefers-reduced-motion: reduce){
  .pca-card,.pca-btn,.pca-seg button,.pca-fig svg *{transition:none!important;animation:none!important}
}