:root {
  --bg: #eceef0;
  --panel: #ffffff;
  --text: #2b2118;
  --muted: #6b6560;
  --line: #dcdfe3;
  --accent: #8a4b22;
  --accent-text: #fffaf3;
  --field: #ffffff;
  /* flat view colours (also read by app.js) */
  --face: #4a2c17;
  --foot: #d9b48a;
  --plate: #efe2cf;
  --paper: #ffffff;
  --thin: #f08c00;
  --gap: #d6336c;
  --kept: #e6c229;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1b1612;
    --panel: #251e18;
    --text: #efe6da;
    --muted: #a8988a;
    --line: #3a3027;
    --accent: #d08a52;
    --accent-text: #1b1612;
    --field: #1b1612;
    --paper: #2e261f;
    --plate: #3d3127;
    --foot: #8c6a48;
    --face: #f2dcc0;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.45 system-ui, -apple-system, "Segoe UI", sans-serif;
}
header {
  display: flex; gap: 12px; align-items: center;
  padding: 14px 20px;
  border-bottom: 1px solid var(--line);
}
header h1 { margin: 0; font-size: 20px; }
header p { margin: 0; color: var(--muted); font-size: 13px; }

main {
  display: grid;
  grid-template-columns: minmax(300px, 380px) 1fr;
  gap: 16px;
  padding: 16px;
  align-items: start;
}
@media (max-width: 820px) {
  main { grid-template-columns: 1fr; }
  .view { order: -1; }
}

.controls { display: flex; flex-direction: column; gap: 12px; }
.controls section, .view {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 14px 16px;
}
.view { position: sticky; top: 16px; }
@media (max-width: 820px) { .view { position: static; } }

h2 { margin: 0 0 10px; font-size: 15px; display: flex; gap: 8px; align-items: center; }
.n {
  display: inline-grid; place-items: center;
  width: 22px; height: 22px; border-radius: 50%;
  background: var(--accent); color: var(--accent-text);
  font-size: 12px;
}
.muted { color: var(--muted); font-size: 13px; margin: 0 0 8px; }
small { display: block; color: var(--muted); font-size: 12px; }

label { display: block; margin: 8px 0; font-size: 14px; }
.slider output { float: right; color: var(--muted); font-variant-numeric: tabular-nums; }
input[type=range] { width: 100%; accent-color: var(--accent); }
input[type=checkbox] { accent-color: var(--accent); margin-right: 6px; }
.check { display: flex; align-items: center; flex-wrap: wrap; gap: 4px; }
input[type=number] {
  width: 70px; padding: 4px 6px;
  border: 1px solid var(--line); border-radius: 6px;
  background: var(--field); color: var(--text); font: inherit;
}
.unit { display: inline-flex; gap: 4px; align-items: center; color: var(--muted); white-space: nowrap; }
.pair { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.pair label .unit { display: flex; margin-top: 2px; }
.row { display: flex; gap: 8px; align-items: center; }
.between { justify-content: space-between; }

.drop {
  display: block; text-align: center; cursor: pointer;
  border: 2px dashed var(--line); border-radius: 8px;
  padding: 16px 10px; margin: 0 0 8px;
}
.drop.over, .drop:hover { border-color: var(--accent); }
.drop input { display: none; }
.drop strong { color: var(--accent); }

button { font: inherit; cursor: pointer; }
.link { background: none; border: 0; color: var(--accent); padding: 0; text-decoration: underline; }
.primary {
  width: 100%; padding: 10px; border: 0; border-radius: 8px;
  background: var(--accent); color: var(--accent-text); font-weight: 600;
}
.primary:disabled { opacity: .45; cursor: default; }
.tips { margin: 8px 0 0; padding-left: 18px; font-size: 13px; color: var(--muted); }
.tips li { margin: 3px 0; }

.tabs { display: flex; gap: 6px; align-items: center; margin-bottom: 10px; }
.tabs button {
  border: 1px solid var(--line); background: none; color: var(--text);
  border-radius: 999px; padding: 4px 14px;
}
.tabs button.on { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
#busy { margin-left: auto; color: var(--muted); font-size: 13px; }

.stage {
  position: relative;
  height: min(62vh, 640px);
  min-height: 300px;
  background: var(--paper);
  border-radius: 8px;
  overflow: hidden;
}
.pane { position: absolute; inset: 0; display: grid; place-items: center; }
.pane[hidden] { display: none; }
/* Flat view scrolls when zoomed in; margin:auto centres it when it fits. */
#flatWrap { display: flex; overflow: auto; padding: 12px; }
#flatWrap[hidden] { display: none; }
#flatWrap.pannable { cursor: grab; }
#flatWrap.panning { cursor: grabbing; user-select: none; }
#flat { margin: auto; flex: none; display: block; }
#flatWrap.zoomed #flat { image-rendering: pixelated; }
.zoom-bar {
  position: absolute; top: 10px; right: 10px; z-index: 2;
  display: flex; gap: 2px; align-items: center;
  background: var(--panel); border: 1px solid var(--line); border-radius: 8px;
  padding: 3px; box-shadow: 0 1px 4px rgb(0 0 0 / .12);
}
.zoom-bar[hidden] { display: none; }
.zoom-bar button {
  min-width: 32px; height: 30px; padding: 0 8px;
  border: 0; border-radius: 6px; background: none; color: var(--text); font-size: 16px;
}
.zoom-bar button:hover:not(:disabled) { background: var(--bg); }
.zoom-bar button:disabled { opacity: .35; cursor: default; }
#zoomFit { font-size: 13px; min-width: 52px; font-variant-numeric: tabular-nums; }
#threeWrap canvas { display: block; }
.empty { position: absolute; color: var(--muted); padding: 20px; text-align: center; }

.legend { display: flex; flex-wrap: wrap; gap: 4px 14px; margin-top: 10px; font-size: 12px; color: var(--muted); }
.legend span[hidden] { display: none; }
.sw { display: inline-block; width: 11px; height: 11px; border-radius: 3px; vertical-align: -1px; margin-right: 3px; border: 1px solid var(--line); }
.sw.face { background: var(--face); }
.sw.foot { background: var(--foot); }
.sw.plate { background: var(--plate); }
.sw.thin { background: var(--thin); }
.sw.gap { background: var(--gap); }
.sw.kept { background: var(--kept); }

#warnings p {
  margin: 10px 0 0; padding: 8px 10px; border-radius: 6px; font-size: 13px;
  border-left: 4px solid var(--thin);
  background: color-mix(in srgb, var(--thin) 12%, transparent);
}
#warnings p.gap { border-color: var(--gap); background: color-mix(in srgb, var(--gap) 12%, transparent); }
#warnings p.kept { border-color: var(--kept); background: color-mix(in srgb, var(--kept) 14%, transparent); }
#warnings p.ok { border-color: #2f9e44; background: color-mix(in srgb, #2f9e44 12%, transparent); }
.note { margin: 10px 0 0; }

footer { padding: 4px 20px 20px; text-align: center; font-size: 13px; color: var(--muted); }
footer a { color: var(--accent); }