/* ============================================================
   Gridfinity Ultimate Designer — design tokens + components
   IBM Plex Sans (UI) / IBM Plex Mono (data). Cool grays + azure.
   ============================================================ */
:root {
  --canvas:      oklch(0.968 0.003 255);
  --panel:       #ffffff;
  --panel-2:     oklch(0.985 0.002 255);
  --sunk:        oklch(0.962 0.004 255);

  --ink:         oklch(0.255 0.012 262);
  --ink-2:       oklch(0.470 0.010 262);
  --ink-3:       oklch(0.615 0.008 262);
  --ink-4:       oklch(0.720 0.006 262);

  --line:        oklch(0.912 0.004 262);
  --line-2:      oklch(0.872 0.005 262);
  --line-3:      oklch(0.820 0.006 262);

  --accent:      oklch(0.560 0.150 252);
  --accent-press:oklch(0.500 0.150 252);
  --accent-ink:  oklch(0.470 0.140 252);
  --accent-weak: oklch(0.958 0.028 252);
  --accent-line: oklch(0.820 0.075 252);

  /* easygrab scoops — warm peach/almond, set apart from the steel-blue merges */
  --scoop:       oklch(0.700 0.110 52);
  --scoop-ink:   oklch(0.530 0.120 48);
  --scoop-soft:  oklch(0.880 0.070 60);
  --scoop-bg:    oklch(0.960 0.038 62);

  --wall:        oklch(0.345 0.012 262);
  --wall-soft:   oklch(0.430 0.011 262);
  --cell:        oklch(0.988 0.002 255);
  --cell-hover:  oklch(0.955 0.010 252);

  --warn:        oklch(0.620 0.150 58);
  --warn-weak:   oklch(0.960 0.035 70);
  --err:         oklch(0.560 0.170 25);
  --ok:          oklch(0.580 0.110 155);

  --code-key:     oklch(0.455 0.145 292);
  --code-string:  oklch(0.420 0.105 155);
  --code-number:  oklch(0.470 0.145 252);
  --code-literal: oklch(0.500 0.145 48);
  --code-section: oklch(0.440 0.115 218);
  --code-comment: oklch(0.560 0.020 262);

  --diff-added:   oklch(0.930 0.060 145);
  --diff-removed: oklch(0.940 0.050 25);
  --diff-changed: oklch(0.950 0.070 95);

  --r-sm: 5px;
  --r-md: 8px;
  --r-lg: 12px;

  --sans: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --rail: 372px;
  --jsonw: 360px;

  --sh-1: 0 1px 1px rgba(20,24,33,.03), 0 1px 2px rgba(20,24,33,.05);
  --sh-2: 0 1px 2px rgba(20,24,33,.04), 0 6px 18px -8px rgba(20,24,33,.16);
}

* { box-sizing: border-box; }
html, body {
  margin: 0; height: 100%;
  background: var(--canvas); color: var(--ink);
  font-family: var(--sans);
  font-size: 14px; line-height: 1.45;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
#root { height: 100%; }
button { font-family: inherit; }
::selection { background: color-mix(in oklab, var(--accent) 22%, transparent); }

/* numeric tabular figures everywhere they appear */
.mono, input.mono { font-family: var(--mono); font-feature-settings: "tnum" 1; }

/* ---------------- App shell ---------------- */
.app {
  display: grid;
  grid-template-columns: var(--rail) minmax(0, 1fr) var(--jsonw);
  height: 100%;
  min-height: 0;
}
.col { min-width: 0; min-height: 0; display: flex; flex-direction: column; height: 100%; }
.col.rail   { border-right: 1px solid var(--line); background: var(--panel); }
.col.center { background: var(--canvas); }
.col.json   { border-left: 1px solid var(--line); background: var(--panel); }

/* top bars share a height for a clean horizon line */
.topbar {
  height: 56px; flex: 0 0 56px;
  display: flex; align-items: center; gap: 10px;
  padding: 0 18px;
  border-bottom: 1px solid var(--line);
}
.scroll { overflow: auto; flex: 1 1 auto; min-height: 0; }
.scroll::-webkit-scrollbar { width: 10px; height: 10px; }
.scroll::-webkit-scrollbar-thumb { background: var(--line-3); border-radius: 10px; border: 3px solid var(--panel); }
.scroll::-webkit-scrollbar-thumb:hover { background: var(--ink-4); }

/* ---------------- Brand / header ---------------- */
.brand { display: flex; align-items: center; gap: 11px; }
.brand .glyph {
  width: 26px; height: 26px; border-radius: 6px;
  border: 1.5px solid var(--ink); position: relative; flex: 0 0 auto;
  background:
    linear-gradient(var(--ink), var(--ink)) center / 1.5px 100% no-repeat,
    linear-gradient(var(--ink), var(--ink)) center / 100% 1.5px no-repeat;
}
.brand h1 { font-size: 14px; font-weight: 600; margin: 0; letter-spacing: -0.01em; }
.brand .sub { font-size: 11px; color: var(--ink-3); margin: 0; font-family: var(--mono); }

/* ---------------- Sections (control rail) ---------------- */
.section { border-bottom: 1px solid var(--line); }
.section-head {
  display: flex; align-items: center; gap: 10px;
  width: 100%; padding: 13px 18px; background: none; border: 0; cursor: pointer;
  text-align: left; color: var(--ink);
}
.section-head:hover { background: var(--panel-2); }
.section-head .chev {
  margin-left: auto; color: var(--ink-4); transition: transform .16s ease; flex: 0 0 auto;
}
.section-head[aria-expanded="false"] .chev { transform: rotate(-90deg); }
.section-title { font-size: 12px; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase; color: var(--ink-2); }
.section-num { font-family: var(--mono); font-size: 11px; color: var(--ink-4); width: 16px; }
.section-body { padding: 4px 18px 18px; display: flex; flex-direction: column; gap: 2px; }

/* master switch row sitting in a section header area */
.master {
  display: flex; align-items: center; gap: 10px;
  padding: 9px 18px 9px 18px; margin: 0 0 6px;
}

/* ---------------- Field rows ---------------- */
.field {
  display: grid; grid-template-columns: 1fr auto; align-items: center;
  gap: 6px 12px; padding: 8px 0; min-height: 38px;
}
.field + .field { border-top: 1px solid var(--line); }
.field .label { display: flex; flex-direction: column; gap: 1px; min-width: 0; }
.field .name { font-size: 13px; color: var(--ink); font-weight: 500; }
.field .hint { font-size: 11.5px; color: var(--ink-3); line-height: 1.35; text-wrap: pretty; }
.field .ctl { display: flex; align-items: center; gap: 8px; justify-self: end; }

/* nested (dependent) group with disclosure */
.nest {
  margin: 2px 0 2px 0; padding-left: 12px;
  border-left: 1.5px solid var(--line);
  display: grid; grid-template-rows: 1fr; transition: opacity .2s ease;
}
.nest.collapsed { display: none; }
.nest .field:first-child { padding-top: 4px; }

/* merge list (Dividers section) */
.mergelist-head {
  display: flex; align-items: center; justify-content: space-between; gap: 8px;
  margin: 14px 0 6px; font-size: 12px; font-weight: 600; color: var(--ink-2);
  letter-spacing: 0.02em; white-space: nowrap;
}
.mergelist-empty { font-size: 12px; color: var(--ink-3); padding: 4px 0 2px; }
.mergelist { display: flex; flex-direction: column; gap: 4px; }
.mergerow {
  display: flex; align-items: center; gap: 8px;
  padding: 6px 8px; border: 1px solid var(--line); border-radius: var(--r-sm);
  background: var(--panel-2); cursor: default;
}
.mergerow.hot { border-color: var(--accent-line); background: var(--accent-weak); }
.mergerow .mrlabel { font-size: 11.5px; color: var(--ink); flex: 1 1 auto; }
.mergerow.hot .mrlabel { color: var(--accent-ink); }
.mergerow .mrsize { font-size: 11px; color: var(--ink-4); }
.mergerow .mrremove {
  border: 0; background: transparent; color: var(--ink-4); cursor: pointer;
  font-size: 16px; line-height: 1; width: 18px; height: 18px; border-radius: 4px; flex: 0 0 auto;
}
.mergerow .mrremove:hover { background: color-mix(in oklab, var(--err) 12%, white); color: var(--err); }

/* ---------------- Toggle switch ---------------- */
.sw {
  --w: 34px; --h: 20px;
  appearance: none; width: var(--w); height: var(--h); border-radius: 999px;
  background: var(--line-3); position: relative; cursor: pointer; flex: 0 0 auto;
  transition: background .16s ease; border: 0;
}
.sw::after {
  content: ""; position: absolute; top: 2px; left: 2px;
  width: 16px; height: 16px; border-radius: 50%; background: #fff;
  box-shadow: 0 1px 2px rgba(0,0,0,.25); transition: transform .16s ease;
}
.sw:checked { background: var(--accent); }
.sw:checked::after { transform: translateX(14px); }
.sw:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.sw:disabled { opacity: .5; cursor: not-allowed; }

/* big master switch */
.sw.lg { --w: 40px; --h: 23px; }
.sw.lg::after { width: 19px; height: 19px; }
.sw.lg:checked::after { transform: translateX(17px); }

/* ---------------- Stepper / number ---------------- */
.stepper { display: inline-flex; align-items: stretch; border: 1px solid var(--line-2); border-radius: var(--r-sm); background: #fff; overflow: hidden; }
.stepper button {
  width: 28px; border: 0; background: #fff; color: var(--ink-2); cursor: pointer;
  font-size: 15px; line-height: 1; display: grid; place-items: center;
}
.stepper button:hover { background: var(--sunk); color: var(--ink); }
.stepper button:active { background: var(--line); }
.stepper button:disabled { color: var(--ink-4); cursor: not-allowed; background: #fff; }
.stepper input {
  width: 46px; border: 0; border-left: 1px solid var(--line); border-right: 1px solid var(--line);
  text-align: center; font-family: var(--mono); font-size: 13px; color: var(--ink);
  font-feature-settings: "tnum" 1; -moz-appearance: textfield;
}
.stepper input::-webkit-outer-spin-button, .stepper input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.stepper input:focus { outline: none; }
.stepper:focus-within { border-color: var(--accent-line); box-shadow: 0 0 0 3px var(--accent-weak); }

.numfield {
  display: inline-flex; align-items: center; gap: 0;
  border: 1px solid var(--line-2); border-radius: var(--r-sm); background: #fff; overflow: hidden;
}
.numfield input {
  width: 64px; border: 0; padding: 6px 8px; text-align: right;
  font-family: var(--mono); font-size: 13px; color: var(--ink); font-feature-settings: "tnum" 1;
}
.numfield input:focus { outline: none; }
.numfield .unit { padding: 0 9px 0 6px; font-family: var(--mono); font-size: 11.5px; color: var(--ink-4); border-left: 1px solid var(--line); align-self: stretch; display: flex; align-items: center; background: var(--panel-2); }
.numfield:focus-within { border-color: var(--accent-line); box-shadow: 0 0 0 3px var(--accent-weak); }

.readout { font-family: var(--mono); font-size: 11.5px; color: var(--ink-4); font-feature-settings: "tnum" 1; white-space: nowrap; }

/* small select (segmented) */
.seg { display: inline-flex; border: 1px solid var(--line-2); border-radius: var(--r-sm); overflow: hidden; background: #fff; }
.seg button {
  border: 0; background: #fff; padding: 5px 10px; font-size: 12px; color: var(--ink-2); cursor: pointer;
  font-family: var(--mono);
}
.seg button + button { border-left: 1px solid var(--line); }
.seg button[aria-pressed="true"] { background: var(--accent); color: #fff; }
.seg button:not([aria-pressed="true"]):hover { background: var(--sunk); }

/* note / hint banners */
.note {
  display: flex; gap: 8px; align-items: flex-start;
  font-size: 12px; line-height: 1.4; padding: 9px 11px; border-radius: var(--r-md);
  margin: 6px 0 2px;
}
.note .ic { flex: 0 0 auto; margin-top: 1px; }
.note.info  { background: var(--accent-weak); color: var(--accent-ink); }
.note.warn  { background: var(--warn-weak); color: oklch(0.46 0.11 58); }
.note.muted { background: var(--sunk); color: var(--ink-3); }
.note .reco { font-family: var(--mono); }

/* disabled section visuals */
.dim { opacity: .45; pointer-events: none; }

/* ---------------- Buttons ---------------- */
.btn {
  display: inline-flex; align-items: center; gap: 7px; justify-content: center;
  border: 1px solid var(--line-2); background: #fff; color: var(--ink);
  border-radius: var(--r-sm); padding: 7px 12px; font-size: 13px; font-weight: 500; cursor: pointer;
  transition: background .12s ease, border-color .12s ease;
}
.btn:hover { background: var(--panel-2); border-color: var(--line-3); }
.btn:active { background: var(--sunk); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-press); border-color: var(--accent-press); }
.btn.sm { padding: 5px 9px; font-size: 12px; }
.btn.icon { padding: 6px; width: 30px; }
.btn.ghost { border-color: transparent; background: transparent; color: var(--ink-2); }
.btn.ghost:hover { background: var(--sunk); }
.btn:disabled { opacity: .5; cursor: not-allowed; }

/* ---------------- Center: editor ---------------- */
.center-wrap { flex: 1 1 auto; min-height: 0; display: flex; flex-direction: column; }
.editor-toolbar {
  height: 56px; flex: 0 0 56px;
  display: flex; align-items: center; gap: 10px; padding: 0 22px;
  border-bottom: 1px solid var(--line); background: var(--panel);
}
.editor-toolbar .spacer { flex: 1 1 auto; }
.tool-label {
  display: inline-flex; align-items: center; gap: 7px; white-space: nowrap;
  font-size: 12.5px; font-weight: 600; color: var(--ink);
}
.tool-label svg { color: var(--ink-3); }
.mode-switch { display: inline-flex; background: var(--sunk); border-radius: var(--r-md); padding: 3px; gap: 2px; }
.mode-switch button {
  border: 0; background: transparent; padding: 6px 14px; border-radius: 6px; font-size: 12.5px; font-weight: 500;
  color: var(--ink-2); cursor: pointer; display: inline-flex; align-items: center; gap: 7px; white-space: nowrap;
}
.mode-switch button[aria-pressed="true"] { background: #fff; color: var(--ink); box-shadow: var(--sh-1); }
.mode-switch button:disabled { color: var(--ink-4); cursor: not-allowed; }

.stage {
  flex: 1 1 auto; min-height: 0; position: relative;
  background:
    radial-gradient(circle at 1px 1px, var(--line) 1px, transparent 0) 0 0 / 22px 22px;
  background-color: var(--canvas);
}
.stage-inner { position: absolute; inset: 20px; display: grid; place-items: center; }

/* editor grid frame: 3×3 — chips · unit ruler · grid */
.editor-frame { display: grid; align-items: center; justify-items: center; }
.ef-cols, .ef-rows { display: grid; }
.ef-grid { display: block; }

/* gridfinity unit rulers — proper |---|---| tick ruler */
.uruler { display: grid; position: relative; }
.uruler-top { align-self: end; }
.uruler-left { justify-self: end; }
.uruler .utick {
  position: relative;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono); font-size: 12px; font-weight: 600;
  color: var(--ink-3); font-feature-settings: "tnum" 1;
}
/* baseline running the length of the ruler, hugging the grid edge */
.uruler-top::after,
.uruler-left::after {
  content: ""; position: absolute; background: var(--ink-3);
}
.uruler-top::after  { left: 0; right: 0; bottom: 0; height: 2px; }
.uruler-left::after { top: 0; bottom: 0; right: 0; width: 2px; }
/* division + end ticks */
.uruler-top .utick::before,
.uruler-top .utick:last-child::after {
  content: ""; position: absolute; bottom: 0; width: 2px; height: 11px; background: var(--ink-3);
}
.uruler-top .utick::before { left: 0; }
.uruler-top .utick:last-child::after { right: 0; }
.uruler-left .utick::before,
.uruler-left .utick:last-child::after {
  content: ""; position: absolute; right: 0; height: 2px; width: 11px; background: var(--ink-3);
}
.uruler-left .utick::before { top: 0; }
.uruler-left .utick:last-child::after { bottom: 0; }
.ucorner {
  align-self: end; justify-self: end;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono); font-size: 11px; font-weight: 600; color: var(--ink-3);
}
.utick-key {
  display: inline-flex; align-items: center; justify-content: center;
  width: 17px; height: 15px; border: 1.5px solid var(--ink-4); border-radius: 3px;
  font-family: var(--mono); font-size: 10px; font-weight: 600; color: var(--ink-3);
}

/* track size chips */
.trk {
  min-width: 0; min-height: 26px; display: flex; align-items: center; justify-content: center;
  position: relative;
}
.trk .chip {
  font-family: var(--mono); font-size: 11px; color: var(--ink-3);
  background: var(--panel); border: 1px solid var(--line-2); border-radius: 999px;
  padding: 2px 9px; cursor: pointer; white-space: nowrap; max-width: none;
  overflow: visible;
}
.trk .chip:hover { border-color: var(--accent-line); color: var(--accent-ink); }
.trk .chip.set { color: var(--accent-ink); border-color: var(--accent-line); background: var(--accent-weak); }
.ef-rows .trk { justify-content: flex-end; padding-right: 2px; }

/* the actual cell grid */
.grid {
  display: grid; background: var(--wall); gap: 0; user-select: none;
  border-radius: 7px; box-shadow: var(--sh-2);
  position: relative;
}
.grid.rounded { border-radius: 12px; }
.cell {
  background: var(--cell); position: relative; overflow: hidden;
  display: grid; place-items: center;
}
.cell .coord {
  font-family: var(--mono); font-size: 10px; color: var(--ink-4);
  opacity: 0; transition: opacity .12s; pointer-events: none;
}
.grid .cell { cursor: crosshair; }
.grid .cell:hover { background: var(--cell-hover); }
.grid .cell:hover .coord { opacity: 1; }
.cell.selecting { background: var(--accent-weak); }
.grid.dragging .cell.selecting { background: color-mix(in oklab, var(--accent) 24%, white); }

.merge-ov {
  position: relative; background: var(--accent-weak);
  border: 1.5px solid var(--accent-line); margin: -0.5px; border-radius: 3px;
  display: grid; place-items: center; pointer-events: none; z-index: 2;
}
.merge-ov .tag {
  font-family: var(--mono); font-size: 10.5px; color: var(--accent-ink); font-feature-settings: "tnum" 1;
}
.merge-ov.hot { background: color-mix(in oklab, var(--accent) 18%, white); z-index: 4; }
.grid.dragging .merge-ov { outline: 4px dashed var(--accent-line); outline-offset: -4px; }

/* ---- easygrab overlay: scoop ramp bands + clickable wall faces ---- */
.eg-overlay { position: absolute; inset: 0; pointer-events: none; z-index: 5; }
.eg-overlay.quiet .scoop-band { opacity: .8; }

/* a configured scoop reads as a warm hatched ramp hugging its wall — the
   peach hue + diagonal hatch set it clearly apart from the steel-blue,
   flat-filled merge regions. Stripes are bold but sparse, and fade out away
   from the wall via a directional mask (set per-band inline). */
.scoop-band {
  position: absolute; pointer-events: none; border-radius: 2px;
  background-color: color-mix(in oklab, var(--scoop) 9%, transparent);
  background-image: repeating-linear-gradient(
    -45deg,
    var(--scoop-ink) 0 2px,
    transparent 2px 9px);
}

.wall-face {
  position: absolute; pointer-events: auto; cursor: pointer; border-radius: 3px;
  background-color: color-mix(in oklab, var(--scoop-soft) 38%, white);
  background-image: repeating-linear-gradient(
    -45deg,
    color-mix(in oklab, var(--scoop-ink) 55%, transparent) 0 2px,
    transparent 2px 9px);
  box-shadow: inset 0 0 0 1px color-mix(in oklab, var(--scoop) 35%, transparent);
  transition: background-color .1s ease, box-shadow .1s ease;
}
.wall-face:hover {
  background-color: color-mix(in oklab, var(--scoop-soft) 72%, white);
  box-shadow: inset 0 0 0 1.5px var(--scoop-ink);
}
.wall-face.on {
  background-color: color-mix(in oklab, var(--scoop-soft) 58%, white);
  box-shadow: inset 0 0 0 1.5px var(--scoop);
}

/* editable radius tag floating at the middle of each clickable face */
.face-radius {
  position: absolute; z-index: 6; pointer-events: auto;
  display: inline-flex; align-items: center; gap: 1px;
  transform: translate(-50%, -50%);
  background: #fff; border: 1px solid var(--scoop); border-radius: 999px;
  padding: 1px 5px; cursor: text;
  font-family: var(--mono); font-size: 10px; line-height: 1.4; color: var(--scoop-ink);
  box-shadow: 0 1px 3px rgba(0,0,0,.16); white-space: nowrap;
}
.face-radius.linked {
  border-style: dashed; border-color: color-mix(in oklab, var(--scoop) 60%, white);
  color: var(--ink-4); background: var(--scoop-bg);
}
.face-radius .fr-input {
  width: 2.1em; border: 0; background: transparent; outline: none; padding: 0;
  font: inherit; color: inherit; text-align: right;
}
.face-radius .fr-u { opacity: .65; font-size: 9px; }
.face-radius .fr-link {
  display: inline-grid; place-items: center; width: 11px; height: 11px; margin-left: 1px;
  opacity: .7;
}

/* legend scoop key */
.legend .eg-key {
  background-color: color-mix(in oklab, var(--scoop) 9%, transparent);
  background-image: repeating-linear-gradient(
    -45deg,
    var(--scoop-ink) 0 2px,
    transparent 2px 9px);
  box-shadow: inset 0 -2px 0 0 var(--scoop);
}

/* easygrab scoop list (Controls) */
.egrow {
  display: flex; align-items: center; gap: 8px;
  padding: 5px 8px; border: 1px solid var(--line); border-radius: var(--r-sm);
  background: var(--panel-2);
}
.egrow .egside {
  flex: 0 0 auto; width: 20px; height: 20px; border-radius: 5px;
  display: grid; place-items: center; font-family: var(--mono); font-size: 11px; font-weight: 600;
  color: #fff; background: var(--accent);
}
.egrow .mrlabel { font-size: 11.5px; color: var(--ink); flex: 1 1 auto; min-width: 0; }
.egrow .numfield input { width: 42px; padding: 5px 6px; }
.egrow .numfield .unit { padding: 0 6px 0 5px; }
.egrow .egtag {
  flex: 0 0 auto; border: 1px solid var(--line-2); background: #fff; cursor: default;
  font-family: var(--mono); font-size: 9.5px; letter-spacing: .03em; text-transform: uppercase;
  color: var(--accent-ink); border-radius: 4px; padding: 2px 5px;
}
.egrow .egtag.def { color: var(--ink-4); cursor: default; }
.egrow .egtag:not(.def) { border-color: var(--accent-line); background: var(--accent-weak); cursor: pointer; }
.egrow .mrremove {
  border: 0; background: transparent; color: var(--ink-4); cursor: pointer;
  font-size: 16px; line-height: 1; width: 18px; height: 18px; border-radius: 4px; flex: 0 0 auto;
}
.egrow .mrremove:hover { background: color-mix(in oklab, var(--err) 12%, white); color: var(--err); }

/* direction D-pad (easygrab All mode) */
.dpad {
  display: grid; grid-template-columns: repeat(3, 26px); grid-template-rows: repeat(3, 26px);
  gap: 3px; grid-template-areas: ". n ." "w c e" ". s .";
}
.dpad button {
  border: 1px solid var(--line-2); background: #fff; border-radius: 6px; cursor: pointer;
  font-size: 14px; line-height: 1; color: var(--ink-2); display: grid; place-items: center; padding: 0;
}
.dpad button:hover { background: var(--sunk); color: var(--ink); }
.dpad button[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: #fff; }
.dpad .d-n { grid-area: n; } .dpad .d-e { grid-area: e; } .dpad .d-s { grid-area: s; } .dpad .d-w { grid-area: w; }
.dpad .d-c {
  grid-area: c; border-radius: 5px; background: var(--sunk);
  box-shadow: inset 0 0 0 1px var(--line);
}

/* legend */
.legend { display: flex; gap: 16px; align-items: center; padding: 11px 22px; border-top: 1px solid var(--line); flex-wrap: wrap; }
.legend .item { display: inline-flex; align-items: center; gap: 7px; font-size: 11.5px; color: var(--ink-3); }
.legend .sw-key { width: 16px; height: 13px; border-radius: 3px; flex: 0 0 auto; }

/* ---------------- Output panel ---------------- */
.output-topbar { justify-content: space-between; gap: 8px; padding-right: 12px; }
.output-title {
  display: inline-flex; align-items: center; gap: 7px; min-width: 0;
  font-size: 13px; font-weight: 600; color: var(--ink-2);
}
.output-title svg { color: var(--ink-3); flex: 0 0 auto; }
.output-tabs {
  display: inline-flex; gap: 2px; padding: 3px;
  border: 1px solid var(--line); border-radius: var(--r-md); background: var(--sunk);
}
.output-tabs button {
  border: 0; border-radius: 5px; background: transparent; color: var(--ink-3);
  padding: 5px 9px; font-family: var(--mono); font-size: 10.5px; font-weight: 600;
  cursor: pointer;
}
.output-tabs button:hover { color: var(--ink); }
.output-tabs button[aria-selected="true"] {
  color: var(--accent-ink); background: #fff; box-shadow: var(--sh-1);
}
.output-tabs button:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.json-body { flex: 1 1 auto; min-height: 0; display: flex; flex-direction: column; padding: 16px 18px; gap: 12px; }
.json-body[hidden] { display: none; }
.output-scroll { overflow-y: auto; }
.code-window-list { display: flex; flex-direction: column; gap: 14px; }
.code-window-group { min-width: 0; display: flex; flex-direction: column; gap: 7px; }
.code-window-group.fill { flex: 1 1 auto; min-height: 0; }
.code-window {
  min-width: 0; display: flex; flex-direction: column; overflow: hidden;
  border: 1px solid var(--line-2); border-radius: var(--r-md); background: var(--panel-2);
  transition: border-color .12s ease, box-shadow .12s ease;
}
.code-window.fill, .code-editor-window { flex: 1 1 auto; min-height: 0; }
.code-window:focus-within {
  border-color: var(--accent-line); box-shadow: 0 0 0 3px var(--accent-weak);
}
.code-window.bad { border-color: color-mix(in oklab, var(--err) 50%, var(--line)); }
.code-window-header {
  min-height: 34px; flex: 0 0 34px; display: flex; align-items: center; justify-content: space-between;
  gap: 8px; padding: 0 6px 0 12px; border-bottom: 1px solid var(--line);
  background: var(--sunk);
}
.code-filename { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font: 600 10.5px var(--mono); color: var(--ink-3); }
.code-copy {
  display: inline-flex; align-items: center; gap: 5px; flex: 0 0 auto;
  border: 1px solid transparent; border-radius: var(--r-sm); padding: 4px 7px;
  background: transparent; color: var(--ink-3); font-size: 10.5px; font-weight: 500; cursor: pointer;
}
.code-copy:hover { border-color: var(--line-2); background: #fff; color: var(--ink); }
.code-copy:active { border-color: var(--accent-line); background: var(--accent-weak); transform: translateY(1px); }
.code-copy.copied {
  color: oklch(0.420 0.105 155); border-color: color-mix(in oklab, var(--ok) 35%, var(--line));
  background: var(--diff-added);
}
.code-copy:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
.syntax-code {
  min-width: 0; max-width: 100%; margin: 0; padding: 14px; overflow: auto;
  font-family: var(--mono); font-size: 12px; line-height: 1.65; color: var(--ink);
  font-feature-settings: "tnum" 1; tab-size: 2; white-space: pre; background: var(--panel-2);
}
.code-window.fill .syntax-code { flex: 1 1 auto; min-height: 0; }
.code-window-list .syntax-code { overflow-y: visible; }
.syntax-code:focus { outline: none; }
.code-line {
  display: block; width: max-content; min-width: calc(100% + 28px); min-height: 1.65em;
  margin: 0 -14px; padding: 0 14px;
}
.code-line.diff-added { animation: diff-added 800ms ease-out both; }
.code-line.diff-removed { animation: diff-removed 800ms ease-out both; }
.code-line.diff-changed { animation: diff-changed 800ms ease-out both; }
@keyframes diff-added {
  0%, 62.5% { background-color: var(--diff-added); }
  100% { background-color: transparent; }
}
@keyframes diff-removed {
  0%, 62.5% { background-color: var(--diff-removed); }
  100% { background-color: transparent; }
}
@keyframes diff-changed {
  0%, 62.5% { background-color: var(--diff-changed); }
  100% { background-color: transparent; }
}
@media (prefers-reduced-motion: reduce) {
  .code-line.diff-added, .code-line.diff-removed, .code-line.diff-changed { animation: none; }
}
.tok-property { color: var(--code-key); }
.tok-string { color: var(--code-string); }
.tok-number { color: var(--code-number); }
.tok-boolean, .tok-null, .tok-keyword { color: var(--code-literal); }
.tok-section { color: var(--code-section); font-weight: 600; }
.tok-comment { color: var(--code-comment); font-style: italic; }
.tok-operator { color: var(--ink-3); }
.code-editor { position: relative; flex: 1 1 auto; min-height: 0; }
.code-editor-auto { flex: 0 0 auto; }
.code-editor-auto .code-editor-input { overflow-y: hidden; }
.code-editor-highlight {
  position: absolute; inset: 0; overflow: hidden; pointer-events: none;
}
.code-editor-input {
  position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; resize: none;
  border: 0; border-radius: 0; padding: 14px; overflow: auto; background: transparent;
  color: transparent; caret-color: var(--ink); -webkit-text-fill-color: transparent;
  font-family: var(--mono); font-size: 12px; line-height: 1.65;
  font-feature-settings: "tnum" 1; tab-size: 2; white-space: pre;
}
.code-editor-input:focus { outline: none; }
.code-editor-input::selection { background: color-mix(in oklab, var(--accent) 24%, transparent); }
.syntax-code::-webkit-scrollbar, .code-editor-input::-webkit-scrollbar, .output-scroll::-webkit-scrollbar { width: 9px; height: 9px; }
.syntax-code::-webkit-scrollbar-thumb, .code-editor-input::-webkit-scrollbar-thumb, .output-scroll::-webkit-scrollbar-thumb { background: var(--line-3); border: 2px solid var(--panel-2); border-radius: 9px; }
.output-hint { margin: 0 1px; color: var(--ink-3); font-size: 11.5px; line-height: 1.4; }
.output-hint code { font-family: var(--mono); font-size: 10.5px; color: var(--ink-2); }
.output-empty {
  flex: 1 1 auto; display: flex; flex-direction: column; justify-content: center; align-items: center;
  gap: 10px; padding: 28px; text-align: center; color: var(--ink-3); font-size: 12px;
  border: 1px dashed var(--line-2); border-radius: var(--r-md); background: var(--panel-2);
}
.output-empty svg { color: var(--ink-4); }
.json-error {
  display: flex; align-items: flex-start; gap: 8px; font-size: 12px; line-height: 1.45;
  font-family: var(--mono); padding: 8px 11px; border-radius: var(--r-md);
  background: color-mix(in oklab, var(--err) 8%, white); color: var(--err);
  border: 1px solid color-mix(in oklab, var(--err) 28%, white);
}
.json-error svg { flex: 0 0 auto; margin-top: 1px; }
.json-actions { display: flex; gap: 8px; flex-direction: column; }
.json-actions .btn { width: 100%; }
.btn.onshape {
  background: oklch(0.62 0.16 145); border-color: oklch(0.62 0.16 145); color: #fff;
}
.btn.onshape:hover { background: oklch(0.56 0.16 145); border-color: oklch(0.56 0.16 145); }
.ver-badge {
  font-family: var(--mono); font-size: 10.5px; font-weight: 600; letter-spacing: .02em;
  background: rgba(255,255,255,.22); color: #fff; border-radius: 999px;
  padding: 1px 7px; margin-left: 2px;
}

/* popover for track editing */
.pop {
  position: absolute; z-index: 40; background: #fff; border: 1px solid var(--line-2);
  border-radius: var(--r-md); box-shadow: var(--sh-2); padding: 12px; width: 220px;
}
.pop h4 { margin: 0 0 9px; font-size: 11px; text-transform: uppercase; letter-spacing: .05em; color: var(--ink-3); }
.pop .seg { width: 100%; margin-bottom: 10px; }
.pop .seg button { flex: 1; }
.pop label { font-size: 11px; color: var(--ink-3); display: block; margin-bottom: 4px; }
.pop input {
  width: 100%; border: 1px solid var(--line-2); border-radius: var(--r-sm); padding: 7px 9px;
  font-family: var(--mono); font-size: 13px; color: var(--ink);
}
.pop input:focus { outline: none; border-color: var(--accent-line); box-shadow: 0 0 0 3px var(--accent-weak); }
.pop .pop-err { color: var(--err); font-size: 11px; margin-top: 6px; min-height: 1em; }

.kbd { font-family: var(--mono); font-size: 10.5px; background: var(--sunk); border: 1px solid var(--line-2); border-bottom-width: 2px; border-radius: 4px; padding: 1px 5px; color: var(--ink-2); }

/* ---------------- Mobile stacking ---------------- */
@media (max-width: 900px) {
  html, body, #root { height: auto; min-height: 100%; }
  body { overflow-x: hidden; }
  .app {
    display: flex; flex-direction: column; width: 100%; height: auto; min-height: 100svh;
  }
  .col { width: 100%; height: auto; }
  .col.rail { border-right: 0; border-bottom: 1px solid var(--line-2); }
  .col.rail .scroll { flex: 0 0 auto; overflow: visible; }
  .col.center {
    height: max(620px, 90svh); border-bottom: 1px solid var(--line-2);
  }
  .col.json {
    height: max(680px, 100svh); border-left: 0; border-top: 0;
  }
  .editor-toolbar {
    height: auto; min-height: 56px; flex: 0 0 auto; flex-wrap: wrap;
    padding: 10px 14px; row-gap: 5px;
  }
  .editor-toolbar .spacer { display: none; }
  .stage { min-height: 390px; }
  .stage-inner { inset: 14px 8px; }
  .legend { gap: 10px 14px; padding: 10px 14px; }
  .json-body { padding: 14px; }
}

@media (max-width: 420px) {
  .topbar { padding-inline: 14px; }
  .output-topbar { padding-right: 10px; }
  .section-head, .master { padding-inline: 14px; }
  .section-body { padding-inline: 14px; }
  .output-tabs button { padding-inline: 8px; }
}