:root {
  --bg: #f4f1ea;
  --panel: #fffdf9;
  --line: #e4ddd0;
  --text: #2b2620;
  --muted: #7a7064;
  --accent: #2f6f8f;
  --accent-soft: #e2eef3;
  --danger: #c8392b;
  --warn: #c98a0b;
  --ok: #2e8b57;
  --board: #efe9dc;
  --grid: rgba(110, 90, 60, 0.13);

  /* Beech track */
  --wood: #ebcd9a;
  --edge: #b5844c;
  --groove: #cfa266;
  --hole: #5b3d22;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  font: 14px/1.4 var(--font);
  color: var(--text);
  background: var(--bg);
  display: flex;
  flex-direction: column;
}

button, select, input { font: inherit; color: inherit; }
button {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 5px 10px;
  cursor: pointer;
}
button:hover { border-color: #cbbfa9; background: #fff; }
button:active { transform: translateY(1px); }
button:disabled { opacity: 0.45; cursor: default; transform: none; }
button.toggle[aria-pressed="true"] { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }
button.danger:hover { border-color: var(--danger); color: var(--danger); }
kbd {
  font: 11px/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  border: 1px solid var(--line);
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 2px 4px;
  background: #fff;
}

/* Toolbar */
.toolbar {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 8px 14px;
  background: var(--panel);
  border-bottom: 1px solid var(--line);
  flex-wrap: wrap;
}
.brand { font-weight: 700; font-size: 17px; display: flex; align-items: center; gap: 8px; letter-spacing: 0.01em; }
.logo {
  width: 22px; height: 22px; border-radius: 50%;
  background: radial-gradient(circle at 50% 50%, var(--bg) 0 5px, var(--wood) 5.5px 10px, var(--edge) 10.5px);
}
.system select { margin-left: 6px; padding: 4px 6px; border-radius: 6px; border: 1px solid var(--line); background: #fff; }
.group { display: flex; gap: 6px; }

main { flex: 1; display: grid; grid-template-columns: 250px 1fr 290px; min-height: 0; }

/* Palette */
.palette {
  background: var(--panel);
  border-right: 1px solid var(--line);
  overflow-y: auto;
  padding: 12px;
}
.orient { display: flex; gap: 6px; margin-bottom: 10px; }
.orient button { flex: 1; }
.palette h3 { font-size: 11px; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); margin: 14px 0 6px; }
.piece-btn {
  display: grid;
  grid-template-columns: 64px 1fr auto;
  align-items: center;
  gap: 8px;
  width: 100%;
  text-align: left;
  padding: 6px 8px;
  margin-bottom: 4px;
}
.piece-btn .piece-icon { width: 64px; height: 40px; }
.piece-btn .name { font-weight: 600; font-size: 13px; }
.piece-btn .dims { color: var(--muted); font-size: 12px; }
.piece-btn kbd { justify-self: end; }
.replace-banner { display: none; background: var(--accent-soft); border: 1px solid var(--accent); color: var(--accent); border-radius: 6px; padding: 6px 8px; margin-bottom: 8px; font-size: 13px; }
.palette.replacing .replace-banner { display: block; }
.palette.replacing .piece-btn { border-color: var(--accent); }

/* Board */
.board-wrap { position: relative; min-width: 0; min-height: 0; background: var(--board); overflow: hidden; }
#board { width: 100%; height: 100%; display: block; touch-action: none; cursor: default; user-select: none; }
#board.panning { cursor: grabbing; }
.grid-line { fill: none; stroke: var(--grid); stroke-width: 1; vector-effect: non-scaling-stroke; }
#board.no-grid #grid { display: none; }

.piece { cursor: pointer; }
.wood { fill: var(--wood); stroke: var(--edge); stroke-width: 0.8; stroke-linejoin: round; }
.groove { fill: none; stroke: var(--groove); stroke-linecap: butt; }
.hole { fill: var(--hole); }
.peg { fill: var(--wood); stroke: var(--edge); stroke-width: 0.8; }
.outline { stroke-width: 2.5; pointer-events: none; }
.outline path { vector-effect: non-scaling-stroke; }
.piece.bad { --wood: #f3b2a6; --edge: var(--danger); }

.ghost { pointer-events: none; }
.ghost-ok { opacity: 0.55; }
.ghost-bad { --wood: #e9604c; --edge: #8e1f14; --groove: #c13f2c; --hole: #6d1a10; opacity: 0.85; }
.gap-line { stroke: var(--danger); stroke-width: 2; stroke-dasharray: 4 3; vector-effect: non-scaling-stroke; }

.tension { stroke: #fff; stroke-width: 1.5; pointer-events: all; }
.gender-hint path { fill: #f2a516; stroke: #7a4b00; stroke-width: 1.5; stroke-linejoin: round; }
.gender-hint text { font: 700 14px var(--font); fill: #3d2600; }

.open-end { cursor: pointer; }
.open-end circle { fill: #fff; stroke: var(--accent); stroke-width: 2; vector-effect: non-scaling-stroke; }
.open-end .chev { fill: none; stroke: var(--accent); stroke-width: 2.5; stroke-linecap: round; stroke-linejoin: round; vector-effect: non-scaling-stroke; }
.open-end:hover circle { fill: var(--accent-soft); }
.open-end.active circle { fill: var(--accent); animation: pulse 1.6s ease-in-out infinite; }
.open-end.active .chev { stroke: #fff; }
@keyframes pulse { 50% { stroke-width: 6; stroke-opacity: 0.35; } }

.empty-hint {
  position: absolute; inset: 0; display: grid; place-items: center; pointer-events: none;
  color: var(--muted); font-size: 15px; text-align: center; padding: 20px;
}
.empty-hint[hidden] { display: none; }
.scalebar { position: absolute; left: 14px; bottom: 12px; font-size: 12px; color: var(--muted); display: flex; align-items: center; gap: 6px; pointer-events: none; }
.scalebar .bar { height: 6px; border: 2px solid var(--muted); border-top: none; }
.status {
  position: absolute; left: 50%; bottom: 12px; transform: translateX(-50%);
  max-width: min(640px, calc(100% - 200px));
  background: var(--panel); border: 1px solid var(--line); border-radius: 8px;
  padding: 7px 12px; box-shadow: 0 2px 10px rgba(60, 40, 10, 0.08);
  opacity: 0; transition: opacity 0.2s; pointer-events: none;
}
.status.show { opacity: 1; }
.status.error { border-color: var(--danger); color: var(--danger); }
.status.ok { border-color: var(--ok); color: var(--ok); }

/* Right panel */
.panel { background: var(--panel); border-left: 1px solid var(--line); overflow-y: auto; }
.panel section { padding: 12px 14px; border-bottom: 1px solid var(--line); }
.panel h2 { font-size: 11px; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); margin: 0 0 8px; }
.muted { color: var(--muted); }
.small { font-size: 12px; }
.sel-name { font-weight: 600; margin-bottom: 8px; }
.btn-row { display: flex; flex-wrap: wrap; gap: 6px; }
.facts, .hints { list-style: none; margin: 0; padding: 0; }
.facts li { display: flex; justify-content: space-between; padding: 2px 0; }
.facts li b { font-weight: 600; }
.hints li { margin-top: 6px; padding: 6px 8px; border-radius: 6px; font-size: 13px; background: #f6f2ea; border-left: 3px solid var(--muted); }
.hints li.warn { border-left-color: var(--warn); background: #fdf5e3; }
.hints li.error { border-left-color: var(--danger); background: #fbebe8; }
.hints li.ok { border-left-color: var(--ok); background: #eaf5ee; }
.parts { width: 100%; border-collapse: collapse; font-size: 13px; }
.parts td { padding: 3px 0; border-bottom: 1px dashed var(--line); }
.parts td:last-child { text-align: right; font-variant-numeric: tabular-nums; }
.parts tr.total td { border-bottom: none; font-weight: 600; padding-top: 6px; }
.settings label { display: flex; justify-content: space-between; align-items: center; margin-bottom: 6px; }
.settings input { width: 64px; padding: 3px 5px; border: 1px solid var(--line); border-radius: 5px; text-align: right; }
.keys { display: grid; grid-template-columns: auto 1fr; gap: 4px 10px; margin: 0; font-size: 13px; }
.keys dt { white-space: nowrap; }
.keys dd { margin: 0; color: var(--muted); }

@media (max-width: 1000px) {
  main { grid-template-columns: 210px 1fr; }
  .panel { display: none; }
}
@media (max-width: 640px) {
  main { grid-template-columns: 1fr; grid-template-rows: 1fr 190px; }
  .palette { order: 2; border-right: none; border-top: 1px solid var(--line); }
  .toolbar { gap: 8px; }
}