/* ─────────────────────────────────────────────────────────────────────────
   Cartographer's Folio — stylesheet
   Aesthetic: medieval atlas, parchment + iron-gall ink + hand-set serif type
   ───────────────────────────────────────────────────────────────────────── */

:root {
  --parchment:       #ede0c4;
  --parchment-light: #f4ead0;
  --parchment-dark:  #c9b894;
  --parchment-ink:   #bca87d;
  --iron-gall:       #2b1810;
  --iron-gall-soft:  #4a3424;
  --sepia:           #6b4423;
  --sepia-soft:      #8a6a44;
  --lapis:           #1d4e89;
  --vermillion:      #d94f04;
  --verdigris:       #43a35f;
  --gold-leaf:       #b8943a;
  --gold-leaf-soft:  #d4b865;

  --serif: 'IM Fell English', 'EB Garamond', Georgia, serif;
  --serif-sc: 'IM Fell English SC', 'IM Fell DW Pica SC', var(--serif);

  --unfold-ease: cubic-bezier(.2, .75, .25, 1);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
  background: #1a1208;
  color: var(--iron-gall);
  font-family: var(--serif);
  font-size: 16px;
  overflow-x: hidden;
}

/* Scrollbar — sepia quill resting in a parchment gutter. */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--sepia) var(--parchment-dark);
}
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track {
  background:
    repeating-linear-gradient(180deg, rgba(107, 68, 35, 0.10) 0 1px, transparent 1px 8px),
    var(--parchment-dark);
  border-left: 1px solid rgba(107, 68, 35, 0.35);
}
::-webkit-scrollbar-thumb {
  background:
    linear-gradient(to right, var(--sepia) 0%, var(--iron-gall-soft) 50%, var(--sepia) 100%);
  border: 2px solid var(--parchment-dark);
  border-radius: 6px;
  box-shadow: inset 0 0 1px rgba(0, 0, 0, 0.4);
}
::-webkit-scrollbar-thumb:hover {
  background:
    linear-gradient(to right, var(--iron-gall-soft) 0%, var(--iron-gall) 50%, var(--iron-gall-soft) 100%);
}
::-webkit-scrollbar-corner {
  background: var(--parchment-dark);
}

body {
  position: relative;
  padding: 36px 48px 28px;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  isolation: isolate;
}

/* ── Parchment background canvas ─────────────────────────────────────────── */
#parchment-bg {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  z-index: -10;
  display: block;
}

/* ── Marginalia overlay (border, compass, sea monster, etc.) ─────────────── */
#marginalia {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
}
#marginalia svg { display: block; }

/* ── Cartouche (title) ───────────────────────────────────────────────────── */
.cartouche {
  text-align: center;
  margin: 0 auto 14px;
  max-width: 780px;
  color: var(--iron-gall);
}
.cartouche-title {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(28px, 4.2vw, 50px);
  letter-spacing: 0.02em;
  margin: 6px 0 4px;
  line-height: 1.05;
}
.cartouche-sub {
  font-style: italic;
  font-size: clamp(13px, 1.3vw, 16px);
  color: var(--sepia);
  margin: 0 0 8px;
  letter-spacing: 0.02em;
}
.cartouche-seed {
  margin: 0;
  font-size: 12px;
  color: var(--sepia-soft);
  letter-spacing: 0.18em;
}
.cartouche-seed .label {
  font-family: var(--serif-sc);
  margin-right: 8px;
  letter-spacing: 0.22em;
}
.cartouche-seed #seed-display {
  font-style: italic;
  color: var(--iron-gall-soft);
  font-size: 14px;
  letter-spacing: 0.18em;
}
.cartouche-rule {
  height: 1px;
  margin: 6px auto;
  width: min(560px, 86%);
  background:
    linear-gradient(to right, transparent, var(--sepia) 12%, var(--sepia) 88%, transparent),
    linear-gradient(to right, transparent, var(--sepia-soft), transparent);
  background-size: 100% 1px, 100% 3px;
  background-position: center, center;
  background-repeat: no-repeat;
  opacity: 0.85;
}
.cartouche-rule + .cartouche-rule { margin-top: 10px; }

/* ── Stage + Triptych ────────────────────────────────────────────────────── */
.stage {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 26px;
  margin: 6px auto 12px;
  width: 100%;
  max-width: 1500px;
  perspective: 1800px;
  perspective-origin: 50% 40%;
  transform-style: preserve-3d;
  min-height: 460px;
}

.panel {
  position: relative;
  flex: 0 0 auto;
  background: var(--parchment-light);
  border: 1px solid var(--parchment-ink);
  box-shadow:
    inset 0 0 32px rgba(120, 90, 50, 0.18),
    0 6px 18px rgba(40, 25, 8, 0.35),
    0 24px 60px rgba(20, 12, 4, 0.45);
  padding: 14px 14px 8px;
  display: flex;
  flex-direction: column;
  align-items: center;
  border-radius: 2px;
  transition: filter 0.6s var(--unfold-ease);
}
.panel::before {
  /* faint inner border / drafting rule */
  content: '';
  position: absolute;
  inset: 6px;
  border: 1px solid rgba(107, 68, 35, 0.22);
  pointer-events: none;
}

/* In SINGLE mode, only center panel is visible. */
.stage[data-mode="single"] .panel-left,
.stage[data-mode="single"] .panel-right {
  display: none;
}
.stage[data-mode="single"] .panel-center {
  transform: none;
}
/* Hide the algo-specific plate in single mode and show a neutral label,
   so a lone maze doesn't masquerade as "A-Star" before the user has solved. */
.stage[data-mode="single"] .panel-center .plate > * { display: none; }
.stage[data-mode="single"] .panel-center .plate-stats { visibility: hidden; }
.stage[data-mode="single"] .panel-center .plate::before {
  content: 'Folio · The Untrod Maze';
  font-family: var(--serif-sc);
  font-size: 12px;
  letter-spacing: 0.28em;
  color: var(--iron-gall);
  display: block;
  flex: 1;
  text-align: center;
}

/* TRIPTYCH mode: side panels exist; unfold animation applied via WAAPI in JS */
.stage[data-mode="triptych"] .panel-left {
  transform-origin: right center;
}
.stage[data-mode="triptych"] .panel-right {
  transform-origin: left center;
}

.panel-canvas-wrap {
  position: relative;
  width: 100%;
  display: block;
  background:
    radial-gradient(ellipse at center, rgba(255,250,235,0.35), transparent 65%),
    rgba(244, 234, 208, 0.55);
  border-radius: 1px;
}
.panel-canvas {
  display: block;
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
.panel-canvas[data-role="walls"]  { position: relative; z-index: 1; }
.panel-canvas[data-role="state"]  { position: absolute; z-index: 2; pointer-events: none; }

/* ── Plate (per-panel header ribbon) ─────────────────────────────────────── */
.plate {
  width: 100%;
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 4px 6px 10px;
  font-family: var(--serif-sc);
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--iron-gall);
  border-bottom: 1px solid rgba(107, 68, 35, 0.35);
  margin-bottom: 8px;
  position: relative;
}
.plate::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -3px;
  height: 1px;
  background: linear-gradient(to right, transparent, var(--sepia-soft), transparent);
}
.plate-roman {
  font-family: var(--serif);
  font-size: 22px;
  font-style: italic;
  color: var(--sepia);
  letter-spacing: 0;
  line-height: 0.8;
}
.plate-name {
  flex: 1;
  font-size: 13px;
  letter-spacing: 0.22em;
  white-space: nowrap;
}
.plate-complexity {
  font-family: var(--serif);
  font-style: italic;
  font-size: 12px;
  color: var(--sepia);
  letter-spacing: 0.04em;
}

.plate-stats {
  margin-top: 8px;
  width: 100%;
  display: flex;
  justify-content: space-around;
  gap: 12px;
  padding: 4px 6px 2px;
  border-top: 1px solid rgba(107, 68, 35, 0.22);
}
.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  font-family: var(--serif);
  color: var(--iron-gall);
}
.stat-label {
  font-family: var(--serif-sc);
  font-size: 9px;
  letter-spacing: 0.22em;
  color: var(--sepia-soft);
}
.stat-val {
  font-size: 18px;
  font-style: italic;
  color: var(--iron-gall);
  font-variant-numeric: oldstyle-nums;
  min-height: 1.2em;
}

/* algo accent for stat values */
.panel[data-algo="bfs"]   .stat-val { color: var(--lapis); }
.panel[data-algo="astar"] .stat-val { color: var(--vermillion); }
.panel[data-algo="dfs"]   .stat-val { color: var(--verdigris); }

/* ── Comparison ribbon ───────────────────────────────────────────────────── */
.ribbon {
  position: relative;
  margin: 14px auto 6px;
  padding: 14px 56px 18px;
  width: min(900px, 92%);
  background:
    repeating-linear-gradient(
      135deg,
      rgba(180, 140, 80, 0.04) 0 6px,
      rgba(180, 140, 80, 0.0) 6px 14px
    ),
    var(--parchment-light);
  border-top: 1px solid rgba(107, 68, 35, 0.42);
  border-bottom: 1px solid rgba(107, 68, 35, 0.42);
  box-shadow: 0 4px 14px rgba(40, 25, 8, 0.32);
  transform-origin: top center;
  animation: ribbonUnfurl 700ms var(--unfold-ease) both;
}
.ribbon[hidden] { display: none; }

.ribbon-curl {
  position: absolute;
  top: 0; bottom: 0;
  width: 40px;
  background:
    radial-gradient(ellipse at left, rgba(60, 40, 15, 0.28), transparent 70%),
    linear-gradient(to right, var(--parchment-dark), var(--parchment-light));
  box-shadow: inset 0 0 12px rgba(60, 40, 15, 0.4);
}
.ribbon-curl-l { left: -22px;  transform: skewY(6deg); border-right: 1px solid rgba(107, 68, 35, 0.5); }
.ribbon-curl-r { right: -22px; transform: skewY(-6deg); border-left: 1px solid rgba(107, 68, 35, 0.5); }

.ribbon-title {
  margin: 0 0 10px;
  text-align: center;
  font-family: var(--serif);
  font-weight: 400;
  font-size: 22px;
  letter-spacing: 0.04em;
}

.ribbon-grid {
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-family: var(--serif);
  color: var(--iron-gall);
}
.ribbon-row {
  display: grid;
  grid-template-columns: 160px 1fr 110px;
  align-items: center;
  gap: 14px;
  padding: 6px 0;
  border-bottom: 1px dotted rgba(107, 68, 35, 0.32);
}
.ribbon-row:last-child { border-bottom: none; }
.ribbon-name {
  font-family: var(--serif-sc);
  font-size: 12px;
  letter-spacing: 0.2em;
  display: flex;
  align-items: baseline;
  gap: 8px;
  color: var(--iron-gall);
}
.ribbon-name .roman {
  font-family: var(--serif);
  font-style: italic;
  font-size: 18px;
  color: var(--sepia);
}
.ribbon-metrics {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 18px;
}
.ribbon-metric {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.ribbon-metric-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.ribbon-metric-label {
  font-family: var(--serif-sc);
  font-size: 9px;
  letter-spacing: 0.22em;
  color: var(--sepia-soft);
}
.ribbon-metric-val {
  font-family: var(--serif);
  font-style: italic;
  font-variant-numeric: oldstyle-nums;
  font-size: 15px;
  color: var(--iron-gall);
}
.ribbon-bar {
  position: relative;
  height: 6px;
  background:
    repeating-linear-gradient(90deg, rgba(107,68,35,0.16) 0 1px, transparent 1px 7px);
  border-bottom: 1px solid rgba(107,68,35,0.28);
}
.ribbon-bar-fill {
  position: absolute;
  inset: 0 auto 0 0;
  width: 0;
  background:
    repeating-linear-gradient(135deg, currentColor 0 2px, transparent 2px 4px),
    currentColor;
  opacity: 0.85;
  transition: width 1100ms var(--unfold-ease);
}
.ribbon-row[data-algo="bfs"]   { color: var(--lapis); }
.ribbon-row[data-algo="astar"] { color: var(--vermillion); }
.ribbon-row[data-algo="dfs"]   { color: var(--verdigris); }
.optimality {
  text-align: center;
  font-family: var(--serif-sc);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--sepia);
}
.optimality[data-opt="yes"] { color: var(--gold-leaf); }
.winner-mark {
  display: inline-block;
  margin-top: 4px;
  font-family: var(--serif);
  font-style: italic;
  font-size: 11px;
  color: var(--gold-leaf);
}

@keyframes ribbonUnfurl {
  from { transform: scaleY(0.05); opacity: 0; }
  60%  { transform: scaleY(1.04); opacity: 1; }
  to   { transform: scaleY(1); opacity: 1; }
}

/* ── Dock (controls) ─────────────────────────────────────────────────────── */
.dock {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 26px;
  padding: 14px 22px;
  margin: 6px auto 0;
  max-width: 1500px;
}
.dock-group {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}

.btn {
  position: relative;
  font-family: var(--serif-sc);
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--iron-gall);
  background: var(--parchment-light);
  border: 1px solid var(--sepia);
  padding: 10px 18px;
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.2s ease, background 0.2s;
  box-shadow:
    inset 0 0 0 2px var(--parchment-light),
    inset 0 0 12px rgba(120, 80, 30, 0.15),
    0 2px 0 var(--sepia);
  border-radius: 1px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.btn:hover:not(:disabled) {
  transform: translateY(-1px);
  background: var(--parchment);
  box-shadow:
    inset 0 0 0 2px var(--parchment-light),
    inset 0 0 16px rgba(120, 80, 30, 0.22),
    0 3px 0 var(--sepia);
}
.btn:active:not(:disabled) {
  transform: translateY(1px);
  box-shadow:
    inset 0 0 0 2px var(--parchment-light),
    inset 0 0 14px rgba(120, 80, 30, 0.3),
    0 1px 0 var(--sepia);
}
.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  filter: saturate(0.5);
}

.btn-primary {
  background:
    radial-gradient(ellipse at 30% 30%, var(--parchment-light), var(--parchment) 70%);
  border-color: var(--iron-gall);
  box-shadow:
    inset 0 0 0 2px var(--parchment-light),
    inset 0 0 12px rgba(120, 80, 30, 0.18),
    0 2px 0 var(--iron-gall);
}
.btn-quill { color: var(--iron-gall); font-style: italic; font-family: var(--serif); }

.btn-seal {
  background:
    radial-gradient(ellipse at 40% 35%, #e76a30, #b53a08 70%, #7a2406);
  color: var(--parchment-light);
  border-color: #5a1c04;
  text-shadow: 0 1px 0 rgba(0,0,0,0.4);
  box-shadow:
    inset 0 0 0 2px rgba(255,200,160,0.28),
    inset 0 0 16px rgba(80, 20, 4, 0.5),
    0 2px 0 #5a1c04;
}
.btn-seal:hover:not(:disabled) {
  background: radial-gradient(ellipse at 40% 30%, #f17a3a, #c5430a 70%, #861f04);
}
.btn-wax {
  font-family: var(--serif);
  font-size: 16px;
  text-shadow: 0 1px 0 rgba(0,0,0,0.6);
}

.btn-ghost {
  background: transparent;
  border: 1px solid var(--sepia-soft);
  box-shadow: none;
  padding: 8px 12px;
  color: var(--iron-gall-soft);
}
.btn-ghost:hover:not(:disabled) {
  background: rgba(120, 80, 30, 0.08);
  border-color: var(--sepia);
  color: var(--iron-gall);
  box-shadow: none;
  transform: none;
}

.dial {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--iron-gall);
  font-family: var(--serif-sc);
  font-size: 11px;
  letter-spacing: 0.2em;
}
.dial-val {
  font-family: var(--serif);
  font-style: italic;
  font-size: 14px;
  color: var(--sepia);
  font-variant-numeric: oldstyle-nums;
  min-width: 36px;
  text-align: right;
}
.dial input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 140px;
  height: 14px;
  background: transparent;
  cursor: pointer;
}
.dial input[type="range"]::-webkit-slider-runnable-track {
  height: 4px;
  background:
    linear-gradient(to right, var(--sepia) 0 100%);
  border-radius: 1px;
  box-shadow: inset 0 0 4px rgba(60,30,10,0.5);
}
.dial input[type="range"]::-moz-range-track {
  height: 4px;
  background: var(--sepia);
  border-radius: 1px;
  box-shadow: inset 0 0 4px rgba(60,30,10,0.5);
}
.dial input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px;
  height: 14px;
  margin-top: -5px;
  background:
    radial-gradient(circle at 30% 30%, var(--gold-leaf-soft), var(--gold-leaf) 70%, #6b4e1c);
  border-radius: 50%;
  border: 1px solid #4a3414;
  box-shadow: 0 1px 2px rgba(0,0,0,0.5), inset 0 1px 1px rgba(255,255,255,0.4);
}
.dial input[type="range"]::-moz-range-thumb {
  width: 14px; height: 14px;
  background: radial-gradient(circle at 30% 30%, var(--gold-leaf-soft), var(--gold-leaf) 70%, #6b4e1c);
  border-radius: 50%;
  border: 1px solid #4a3414;
}

/* ── Legend ──────────────────────────────────────────────────────────────── */
.legend {
  display: flex;
  justify-content: center;
  gap: 28px;
  padding: 6px 0 18px;
  font-family: var(--serif);
  font-style: italic;
  color: var(--iron-gall-soft);
  font-size: 13px;
  letter-spacing: 0.04em;
}
.legend-item { display: inline-flex; align-items: center; gap: 8px; }
.swatch {
  display: inline-block;
  width: 18px; height: 12px;
  border: 1px solid rgba(43, 24, 16, 0.5);
  border-radius: 1px;
}
.swatch-bfs   { background:
  repeating-radial-gradient(circle at 4px 4px, var(--lapis) 0 1px, transparent 1.5px 6px),
  rgba(244, 234, 208, 0.5);
}
.swatch-astar { background: var(--vermillion); }
.swatch-dfs   { background:
  repeating-linear-gradient(45deg, var(--verdigris) 0 2px, transparent 2px 5px),
  rgba(244, 234, 208, 0.5);
}

/* ── Responsive fallback: vertical stack ─────────────────────────────────── */
@media (max-width: 1100px) {
  body { padding: 24px 18px; }
  .stage {
    flex-direction: column;
    perspective-origin: 50% 50%;
    gap: 18px;
  }
  .stage[data-mode="triptych"] .panel-left  { transform-origin: center bottom; }
  .stage[data-mode="triptych"] .panel-right { transform-origin: center top; }
  .ribbon-grid {
    grid-template-columns: 110px 1fr 70px 70px 70px;
    font-size: 13px;
  }
}