/* iCaviot — design system tokens */
  :root {
    /* Surfaces — workshop dark, layered for depth */
    --s0: #08080A;
    --s1: #0E0E11;
    --s2: #15151A;
    --s3: #1C1C22;
    --s4: #24242B;
    --s5: #2D2D35;
    /* Borders */
    --b1: rgba(255,255,255,0.06);
    --b2: rgba(255,255,255,0.10);
    --b3: rgba(255,255,255,0.16);
    /* Text */
    --t1: #F4F2EE;
    --t2: #A8A6A0;
    --t3: #6B6A65;
    --t4: #46453F;
    /* Brand + signal */
    --accent: #FF6B00;
    --accent-hover: #FF8533;
    --accent-soft: rgba(255,107,0,0.14);
    --accent-glow: rgba(255,107,0,0.35);
    --success: #2BD17E;
    --warning: #FFB020;
    --danger: #FF5757;
    /* Legacy aliases — kept so existing JS `var(--accent-2)`, `var(--danger)` still resolve */
    --accent-2: #2BD17E;
    --bg: var(--s0);
    --panel: var(--s1);
    --panel-2: var(--s3);
    --line: var(--b1);
    --text: var(--t1);
    --muted: var(--t2);
    /* Type */
    /* System font stacks keep the interface usable entirely offline. */
    --sans: "Segoe UI Variable", "Segoe UI", -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    --mono: "Cascadia Mono", "SFMono-Regular", Consolas, ui-monospace, monospace;
    --display: Impact, Haettenschweiler, "Arial Narrow Bold", var(--sans);
    /* Layout */
    --topbar-h: 56px;
    --status-h: 36px;
    --sidebar-w: 340px;
  }


  /* ─── iCaviot — production design system (overrides) ─────────────── */

  /* Reset / base */
  *, *::before, *::after { box-sizing: border-box; }
  html, body { margin: 0; padding: 0; height: 100vh; overflow: hidden; }
  body {
    background: var(--s0);
    color: var(--t1);
    font-family: var(--sans);
    font-size: 13px;
    line-height: 1.45;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    font-feature-settings: 'cv11', 'ss01';
  }
  ::selection { background: var(--accent); color: #000; }
  button, input, select, textarea { font-family: inherit; color: inherit; }
  kbd {
    font-family: var(--mono);
    font-size: 10px;
    padding: 1px 4px;
    border-radius: 3px;
    background: rgba(0,0,0,0.18);
    margin-left: 4px;
    opacity: 0.7;
  }

  /* ─── Shell ─── */
  .shell {
    display: grid;
    grid-template-rows: var(--topbar-h) 1fr var(--status-h);
    height: 100vh;
  }
  .app {
    display: grid;
    grid-template-columns: var(--sidebar-w) 1fr;
    overflow: hidden;
    min-height: 0;
  }

  /* ─── Top bar ─── */
  .topbar {
    display: grid;
    grid-template-columns: var(--sidebar-w) 1fr auto;
    align-items: center;
    background: var(--s2);
    border-bottom: 1px solid var(--b1);
    padding: 0 16px 0 20px;
    gap: 16px;
    -webkit-app-region: drag;
  }
  .topbar > * { -webkit-app-region: no-drag; }
  .brand {
    font-family: var(--display);
    font-size: 22px;
    letter-spacing: 0.02em;
    line-height: 1;
    color: var(--t1);
    text-decoration: none;
    display: flex;
    align-items: baseline;
    gap: 10px;
  }
  .brand span { color: var(--accent); }
  .brand small {
    font-family: var(--mono);
    font-size: 9px;
    letter-spacing: 0.14em;
    color: var(--t3);
    text-transform: uppercase;
    font-weight: 500;
  }

  /* Mode switcher — center */
  .mode-pills {
    display: inline-flex;
    background: var(--s3);
    border: 1px solid var(--b1);
    border-radius: 8px;
    padding: 3px;
    gap: 2px;
    margin: 0 auto;
    position: relative;
  }
  .mode-pills input { position: absolute; opacity: 0; pointer-events: none; }
  .mode-pills label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    font-size: 12.5px;
    font-weight: 500;
    color: var(--t2);
    cursor: pointer;
    border-radius: 5px;
    transition: background 140ms ease, color 140ms ease;
    user-select: none;
    margin: 0;
  }
  .mode-pills label:hover { color: var(--t1); }
  .mode-pills input:checked + label {
    background: var(--s5);
    color: var(--accent);
    box-shadow: inset 0 0 0 1px var(--b2);
  }
  .mode-pills .glyph { opacity: 0.65; font-size: 11px; }

  .top-actions { display: inline-flex; gap: 8px; align-items: center; }
  .mobile-settings-btn { display: none; }

  /* ─── Buttons ─── */
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    height: 32px;
    padding: 0 14px;
    border-radius: 6px;
    font-size: 12.5px;
    font-weight: 500;
    border: 1px solid transparent;
    cursor: pointer;
    transition: background 140ms ease, border-color 140ms ease, transform 80ms ease, opacity 140ms ease, box-shadow 140ms ease;
    white-space: nowrap;
    font-family: inherit;
  }
  .btn:disabled { opacity: 0.4; cursor: not-allowed; }
  .btn-primary {
    background: var(--accent);
    color: #000;
    font-weight: 600;
    box-shadow: 0 0 0 0 var(--accent-glow);
  }
  .btn-primary:hover:not(:disabled) {
    background: var(--accent-hover);
    box-shadow: 0 4px 14px -2px var(--accent-glow);
  }
  .btn-primary:active:not(:disabled) { transform: translateY(1px); }
  .btn-ghost {
    background: transparent;
    color: var(--t2);
    border-color: var(--b2);
  }
  .btn-ghost:hover:not(:disabled) {
    background: var(--s3);
    color: var(--t1);
    border-color: var(--b3);
  }
  .btn-sm { height: 26px; padding: 0 10px; font-size: 11.5px; }
  .icon-btn {
    background: var(--s3);
    border: 1px solid var(--b1);
    color: var(--t2);
    width: 100%; height: 30px;
    border-radius: 6px;
    cursor: pointer;
    transition: background 140ms ease, color 140ms ease, border-color 140ms ease;
    display: inline-flex; align-items: center; justify-content: center;
    font-size: 13px;
    font-family: inherit;
  }
  .icon-btn:hover:not(:disabled) { background: var(--s4); color: var(--t1); border-color: var(--b2); }
  .icon-btn:disabled { opacity: 0.35; cursor: not-allowed; }

  /* ─── Sidebar ─── */
  .sidebar {
    background: var(--s1);
    border-right: 1px solid var(--b1);
    overflow-y: auto;
    overflow-x: hidden;
    padding: 0;
    display: flex;
    flex-direction: column;
    /* override old .sidebar rules */
    width: auto;
  }
  .sidebar::-webkit-scrollbar { width: 8px; }
  .sidebar::-webkit-scrollbar-track { background: transparent; }
  .sidebar::-webkit-scrollbar-thumb { background: var(--b2); border-radius: 4px; }
  .sidebar::-webkit-scrollbar-thumb:hover { background: var(--b3); }

  /* Panel = sidebar section (overrides old .panel) */
  .panel {
    padding: 14px 16px;
    border-bottom: 1px solid var(--b1);
    background: transparent;
  }
  .panel:last-of-type { border-bottom: none; }
  .panel-label {
    font-family: var(--mono);
    font-size: 10px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--t3);
    margin-bottom: 10px;
    font-weight: 500;
  }

  /* ─── Fields ─── */
  .field { display: grid; gap: 6px; margin-bottom: 10px; }
  .field:last-child { margin-bottom: 0; }
  .field-label {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    font-size: 12px;
    color: var(--t2);
    margin: 0;
  }
  .field-label .v {
    font-family: var(--mono);
    font-size: 11.5px;
    color: var(--t1);
    font-variant-numeric: tabular-nums;
    letter-spacing: 0.02em;
  }
  .field-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
  }

  /* ─── Inputs ─── */
  .sidebar input[type=text],
  .sidebar input[type=number],
  .sidebar select {
    width: 100%;
    height: 30px;
    background: var(--s3);
    border: 1px solid var(--b1);
    color: var(--t1);
    border-radius: 5px;
    padding: 0 8px;
    font-size: 12.5px;
    font-feature-settings: 'tnum';
    transition: border-color 120ms ease, background 120ms ease, box-shadow 120ms ease;
    -webkit-appearance: none;
    appearance: none;
    font-family: inherit;
    min-height: 0;
  }
  .sidebar input[type=text]:hover,
  .sidebar input[type=number]:hover,
  .sidebar select:hover { background: var(--s4); }
  .sidebar input[type=text]:focus,
  .sidebar input[type=number]:focus,
  .sidebar select:focus {
    outline: none;
    border-color: var(--accent);
    background: var(--s5);
    box-shadow: 0 0 0 3px var(--accent-soft);
  }
  .sidebar select {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6'%3E%3Cpath fill='%23A8A6A0' d='M5 6L0 0h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 10px center;
    padding-right: 26px;
  }

  /* ─── Range sliders ─── */
  .sidebar input[type=range] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 18px;
    background: transparent;
    cursor: pointer;
    padding: 0;
    margin: 0;
  }
  .sidebar input[type=range]::-webkit-slider-runnable-track {
    height: 4px;
    background: var(--s3);
    border: 1px solid var(--b1);
    border-radius: 3px;
  }
  .sidebar input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 14px; height: 14px;
    background: var(--t1);
    border: 2px solid var(--s1);
    border-radius: 50%;
    margin-top: -6px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.4);
    transition: transform 120ms ease, background 120ms ease;
  }
  .sidebar input[type=range]:hover::-webkit-slider-thumb { background: var(--accent); transform: scale(1.15); }
  .sidebar input[type=range]:active::-webkit-slider-thumb { background: var(--accent); transform: scale(1.2); }
  .sidebar input[type=range]::-moz-range-track {
    height: 4px;
    background: var(--s3);
    border: 1px solid var(--b1);
    border-radius: 3px;
  }
  .sidebar input[type=range]::-moz-range-thumb {
    width: 12px; height: 12px;
    background: var(--t1);
    border: 2px solid var(--s1);
    border-radius: 50%;
    box-shadow: 0 1px 3px rgba(0,0,0,0.4);
    transition: background 120ms ease, transform 120ms ease;
  }
  .sidebar input[type=range]:hover::-moz-range-thumb { background: var(--accent); transform: scale(1.15); }

  /* ─── Big slider (logo size, depth) ─── */
  .big-field { margin-bottom: 16px; }
  .big-field:last-of-type { margin-bottom: 10px; }
  .big-field-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 6px;
  }
  .big-field-label {
    font-family: var(--mono);
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--t3);
    font-weight: 500;
  }
  .big-field-value {
    font-family: var(--mono);
    font-variant-numeric: tabular-nums;
    font-size: 22px;
    line-height: 1;
    color: var(--t1);
    letter-spacing: -0.01em;
    font-weight: 400;
  }
  .big-field-value .unit { font-size: 12px; color: var(--t3); margin-left: 2px; }
  .big-field input[type=range] { height: 22px; }
  .big-field input[type=range]::-webkit-slider-runnable-track { height: 6px; }
  .big-field input[type=range]::-webkit-slider-thumb {
    width: 18px; height: 18px;
    margin-top: -7px;
    background: var(--accent);
    border-color: var(--s1);
    box-shadow: 0 1px 4px var(--accent-glow);
  }
  .big-field input[type=range]:hover::-webkit-slider-thumb,
  .big-field input[type=range]:active::-webkit-slider-thumb { transform: scale(1.1); background: var(--accent); }
  .big-field-context {
    display: flex;
    justify-content: space-between;
    margin-top: 4px;
    font-family: var(--mono);
    font-size: 10px;
    color: var(--t3);
    letter-spacing: 0.04em;
  }
  .big-field-context span:nth-child(2) { color: var(--t2); }

  /* ─── Pill toggle (Raised / Carved) ───
     Must be flex (not grid): hidden radios + labels are siblings. With
     grid-template-columns:1fr 1fr the four children auto-place into a
     2×2, stacking both labels in the right column and leaving the left
     half empty — buttons look broken / only half-clickable. Flex keeps
     absolute radios out of layout so the two labels sit side-by-side. */
  .pill-toggle {
    display: flex;
    position: relative;
    background: var(--s3);
    border: 1px solid var(--b1);
    border-radius: 6px;
    padding: 2px;
    gap: 2px;
    margin-top: 4px;
  }
  .pill-toggle input {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
    margin: 0;
    pointer-events: none;
  }
  .pill-toggle label {
    flex: 1 1 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 7px 6px;
    font-size: 12px;
    color: var(--t2);
    cursor: pointer;
    border-radius: 4px;
    transition: background 140ms ease, color 140ms ease, box-shadow 140ms ease;
    user-select: none;
    font-weight: 500;
    margin: 0;
    min-width: 0;
  }
  .pill-toggle label:hover { color: var(--t1); }
  .pill-toggle input:checked + label {
    background: var(--s5);
    color: var(--accent);
    box-shadow: inset 0 0 0 1px var(--b2);
  }
  .pill-toggle input:focus-visible + label {
    outline: 2px solid var(--accent);
    outline-offset: 1px;
  }

  /* ─── Checkboxes (.check) ─── */
  .check {
    display: flex;
    align-items: center;
    gap: 9px;
    cursor: pointer;
    padding: 4px 0;
    font-size: 12px;
    color: var(--t1);
    user-select: none;
    line-height: 1.35;
  }
  .check input[type=checkbox] {
    -webkit-appearance: none;
    appearance: none;
    width: 14px; height: 14px;
    background: var(--s3);
    border: 1px solid var(--b2);
    border-radius: 3px;
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
    transition: background 120ms ease, border-color 120ms ease;
    margin: 0;
  }
  .check input[type=checkbox]:hover { border-color: var(--b3); }
  .check input[type=checkbox]:checked {
    background: var(--accent);
    border-color: var(--accent);
  }
  .check input[type=checkbox]:checked::after {
    content: '';
    position: absolute;
    left: 3px; top: 0;
    width: 4px; height: 8px;
    border: solid #000;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
  }
  .check span { line-height: 1.35; }

  /* ─── Drop area ─── */
  .drop {
    background: var(--s2);
    border: 1px dashed var(--b2);
    border-radius: 6px;
    padding: 14px 12px;
    text-align: center;
    cursor: pointer;
    transition: border-color 140ms ease, background 140ms ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    min-height: 0;
  }
  .drop:hover, .drop:focus-visible {
    border-color: var(--accent);
    background: var(--accent-soft);
    outline: none;
  }
  .drop.dragover {
    border-color: var(--accent);
    border-style: solid;
    background: var(--accent-soft);
    box-shadow: 0 0 0 3px var(--accent-soft);
  }
  .drop .glyph { font-size: 18px; color: var(--t2); }
  .drop strong { font-size: 12.5px; color: var(--t1); font-weight: 500; }
  .drop small { font-size: 10.5px; color: var(--t3); }
  .filename {
    font-family: var(--mono);
    font-size: 10.5px;
    color: var(--accent);
    padding: 8px 0 0;
    word-break: break-all;
    line-height: 1.3;
  }
  .img-tools {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 4px;
    margin-top: 8px;
  }
  .source-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 6px;
    margin-top: 8px;
  }
  .divider {
    height: 1px;
    background: var(--b1);
    margin: 10px 0;
  }
  .bg-color {
    display: grid;
    grid-template-columns: 22px 1fr auto auto;
    align-items: center;
    gap: 6px;
  }
  .swatch {
    width: 22px; height: 22px;
    border-radius: 4px;
    border: 1px solid var(--b2);
    background: #fff;
  }
  .swatch-label {
    font-family: var(--mono);
    font-size: 10.5px;
    color: var(--t2);
    letter-spacing: 0.04em;
  }

  /* ─── Canvas ─── */
  .canvas {
    position: relative;
    background:
      radial-gradient(80% 60% at 50% 40%, rgba(255,107,0,0.04) 0%, transparent 70%),
      var(--s0);
    overflow: hidden;
    min-height: 0;
  }
  #threeContainer {
    width: 100%;
    height: 100%;
    cursor: grab;
  }
  #threeContainer:active { cursor: grabbing; }
  .canvas-meta {
    position: absolute;
    top: 14px;
    left: 16px;
    display: flex;
    gap: 8px;
    align-items: center;
    font-family: var(--mono);
    font-size: 10.5px;
    color: var(--t3);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    pointer-events: none;
    z-index: 5;
  }
  .canvas-meta .dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 0 4px var(--accent-soft);
    animation: pulse 2.4s ease-in-out infinite;
  }
  @keyframes pulse {
    0%, 100% { box-shadow: 0 0 0 0 var(--accent-soft); }
    50% { box-shadow: 0 0 0 6px transparent; }
  }
  .canvas-hint {
    position: absolute;
    top: 14px;
    right: 118px; /* leave room for Reset view button */
    font-family: var(--mono);
    font-size: 10.5px;
    color: var(--t3);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    pointer-events: none;
    z-index: 5;
    max-width: min(420px, calc(100% - 140px));
    text-align: right;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
  #resetViewBtn {
    position: absolute;
    top: 14px;
    right: 14px;
    z-index: 6;
  }

  /* ─── Heightmap mini-map ─── */
  .hm-mini {
    position: absolute;
    bottom: 16px;
    right: 16px;
    width: 180px;
    background: rgba(14,14,17,0.85);
    backdrop-filter: blur(12px) saturate(150%);
    -webkit-backdrop-filter: blur(12px) saturate(150%);
    border: 1px solid var(--b1);
    border-radius: 8px;
    padding: 8px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.4);
    z-index: 10;
  }
  .hm-mini-head {
    display: flex;
    justify-content: space-between;
    font-family: var(--mono);
    font-size: 9.5px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--t3);
    margin-bottom: 6px;
  }
  .hm-mini-canvas-wrap {
    position: relative;
    aspect-ratio: 4/3;
    background: #000;
    border-radius: 4px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
  }
  #heightmapCanvas {
    max-width: 100%;
    max-height: 100%;
    image-rendering: pixelated;
  }
  .hm-mini-empty {
    color: var(--t4);
    font-size: 10px;
    position: absolute;
  }

  /* ─── Status strip ─── */
  .status-strip {
    background: var(--s2);
    border-top: 1px solid var(--b1);
    display: flex;
    align-items: center;
    padding: 0 16px;
    gap: 22px;
    font-family: var(--mono);
    font-size: 10.5px;
    color: var(--t2);
    letter-spacing: 0.04em;
  }
  .stat-cell {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    white-space: nowrap;
  }
  .stat-cell .k {
    color: var(--t3);
    text-transform: uppercase;
    letter-spacing: 0.12em;
    font-size: 9.5px;
  }
  .stat-cell .v {
    color: var(--t1);
    font-variant-numeric: tabular-nums;
  }
  .status-right { margin-left: auto; display: inline-flex; gap: 12px; align-items: center; }
  .tips-link {
    background: transparent;
    border: none;
    color: var(--t2);
    font-family: var(--mono);
    font-size: 10.5px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    cursor: pointer;
    padding: 0;
    transition: color 140ms ease;
  }
  .tips-link:hover { color: var(--t1); }

  /* ─── Tips drawer ─── */
  .tips-drawer {
    position: fixed;
    right: 16px;
    bottom: calc(var(--status-h) + 12px);
    width: 380px;
    max-height: 70vh;
    overflow-y: auto;
    background: var(--s2);
    border: 1px solid var(--b2);
    border-radius: 10px;
    padding: 18px 20px;
    box-shadow: 0 12px 40px rgba(0,0,0,0.6);
    z-index: 60;
    font-size: 12.5px;
    line-height: 1.6;
    color: var(--t2);
  }
  .tips-drawer.hidden { display: none; }
  .tips-drawer strong { color: var(--t1); font-weight: 600; display: block; margin-top: 12px; }
  .tips-drawer strong:first-child { margin-top: 0; }
  .tips-drawer ol, .tips-drawer ul { margin: 8px 0 14px; padding-left: 20px; }
  .tips-drawer li { margin-bottom: 4px; }
  .tips-drawer em { color: var(--accent); font-style: normal; }

  /* ─── Toast (override old) ─── */
  .toast {
    position: fixed;
    bottom: calc(var(--status-h) + 16px);
    left: 50%;
    transform: translateX(-50%) translateY(8px);
    background: var(--s4);
    border: 1px solid var(--b2);
    color: var(--t1);
    padding: 10px 16px;
    border-radius: 8px;
    font-size: 12.5px;
    opacity: 0;
    pointer-events: none;
    transition: opacity 200ms ease, transform 200ms ease;
    z-index: 200;
    box-shadow: 0 12px 30px rgba(0,0,0,0.5);
  }
  .toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
  .toast.error { border-color: var(--danger); color: var(--danger); }
  .toast.success { border-color: var(--success); color: var(--success); }

  /* ─── Modal (override old) ─── */
  .modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.7);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 300;
    padding: 24px;
  }
  .modal-overlay.hidden { display: none; }
  .modal-box {
    background: var(--s1);
    border: 1px solid var(--b2);
    border-radius: 10px;
    max-width: 720px;
    width: 100%;
    max-height: 86vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    box-shadow: 0 24px 60px rgba(0,0,0,0.6);
  }
  .modal-head {
    padding: 14px 18px;
    border-bottom: 1px solid var(--b1);
    display: flex;
    align-items: center;
    justify-content: space-between;
  }
  .modal-head h3 {
    margin: 0;
    font-size: 12px;
    font-family: var(--mono);
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--t1);
    font-weight: 500;
  }
  .modal-close {
    background: transparent;
    border: 1px solid var(--b2);
    color: var(--t2);
    width: 28px; height: 28px;
    border-radius: 5px;
    font-size: 16px;
    cursor: pointer;
    line-height: 1;
    transition: color 140ms, border-color 140ms;
    font-family: inherit;
  }
  .modal-close:hover { color: var(--accent); border-color: var(--accent); }
  .modal-body { padding: 18px; overflow-y: auto; }
  .pattern-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 10px;
  }
  .pattern-card {
    background: var(--s2);
    border: 1px solid var(--b1);
    border-radius: 6px;
    padding: 8px;
    cursor: pointer;
    text-align: center;
    transition: border-color 140ms, transform 120ms ease;
    user-select: none;
  }
  .pattern-card:hover { border-color: var(--accent); transform: translateY(-1px); }
  .pattern-card canvas {
    width: 100%;
    aspect-ratio: 1;
    background: #fff;
    border-radius: 4px;
    margin-bottom: 6px;
    display: block;
  }
  .pattern-card .name { font-size: 12px; color: var(--t1); font-weight: 500; }
  .pattern-card .desc { font-size: 10.5px; color: var(--t3); margin-top: 2px; line-height: 1.3; }

  /* ─── Utility ─── */
  .muted-tip { font-size: 11px; color: var(--t3); line-height: 1.45; margin: 6px 0 0; }
  details summary { cursor: pointer; font-size: 11px; color: var(--t3); padding: 4px 0; transition: color 140ms ease; }
  details summary:hover { color: var(--t1); }
  details > div { margin-top: 6px; display: grid; gap: 6px; }

  /* Hide unused legacy nodes still in DOM */
  #advancedToggle, #advancedContent, #stats { display: none !important; }

  /* Responsive: collapse sidebar on narrow viewports */
  @media (max-width: 900px) {
    :root { --topbar-h: 104px; }
    .topbar {
      grid-template-columns: 1fr auto auto;
      grid-template-rows: 52px 44px;
      gap: 0 8px;
      padding: 0 10px 8px 14px;
      overflow: visible;
    }
    .brand small, .brand .version-badge { display: none; }
    .mobile-settings-btn { display: inline-flex; width: auto; padding: 0 10px; }
    .top-actions { gap: 5px; }
    .top-actions .btn { padding-left: 9px; padding-right: 9px; }
    .top-actions kbd { display: none; }
    .topbar .mode-pills {
      grid-column: 1 / -1;
      grid-row: 2;
      margin: 0;
      width: 100%;
      display: grid;
      grid-template-columns: repeat(3, 1fr);
    }
    .mode-pills label { justify-content: center; padding: 6px 5px; }
    .app { grid-template-columns: 1fr; }
    .sidebar {
      position: absolute;
      top: var(--topbar-h);
      bottom: var(--status-h);
      left: 0;
      width: min(380px, 92vw);
      z-index: 40;
      box-shadow: 0 8px 30px rgba(0,0,0,0.5);
      transform: translateX(-105%);
      transition: transform 180ms ease;
    }
    body.mobile-settings-open .sidebar { transform: translateX(0); }
    .hm-mini { max-width: 34vw; }
  }
  .axis-legend {
    position: absolute;
    left: 16px;
    bottom: 16px;
    z-index: 5;
    display: flex;
    gap: 9px;
    padding: 5px 8px;
    border-radius: 5px;
    background: rgba(8,8,10,0.72);
    border: 1px solid var(--b1);
    font: 10px var(--mono);
    pointer-events: none;
  }
  .axis-x { color: #ff4d4d; }
  .axis-y { color: #55dd77; }
  .axis-z { color: #4d8dff; }
  @media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation-duration: 0ms !important; transition-duration: 0ms !important; }
  }

  /* ─── Overflow containment ───
     After an image upload the status bar fills with nowrap stat cells and the
     3D canvas gets a fixed pixel size. Each .shell row is a grid item with the
     default min-width:auto, so it would grow to that content width, overflow
     the viewport, and drag the right-aligned topbar export buttons off-screen
     (where overflow:hidden clipped them). These rules let the rows shrink and
     keep the buttons reachable at any window width. */
  .shell > * { min-width: 0; }
  .topbar { overflow: hidden; }
  .status-strip { overflow-x: auto; overflow-y: hidden; }
  #threeContainer > canvas { max-width: 100%; }

  /* Busy state while the heightmap / mesh rebuilds */
  body.is-rebuilding { cursor: progress; }
  body.is-rebuilding .sidebar { pointer-events: none; opacity: 0.92; }
  .stat-cell .v.warn { color: var(--warning); }
  .stat-cell .v.preview-tag { color: var(--warning); }
  .stat-cell .v.export-tag { color: var(--success); }



/* v2 extras */
.version-badge {
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.12em;
  color: var(--accent);
  border: 1px solid rgba(255,107,0,0.35);
  padding: 2px 6px;
  border-radius: 4px;
  margin-left: 6px;
  vertical-align: middle;
}
.fit-ring-btn {
  width: 100%;
  margin-top: 8px;
  background: linear-gradient(180deg, rgba(255,107,0,0.22), rgba(255,107,0,0.10));
  border: 1px solid rgba(255,107,0,0.45);
  color: var(--t1);
  font-weight: 600;
}
.fit-ring-btn:hover { border-color: var(--accent); background: rgba(255,107,0,0.28); }
details.adv {
  border-top: 1px solid var(--b1);
  margin-top: 8px;
  padding-top: 6px;
}
details.adv > summary {
  cursor: pointer;
  color: var(--t2);
  font-size: 11.5px;
  font-weight: 500;
  list-style: none;
  padding: 6px 0;
  user-select: none;
}
details.adv > summary::-webkit-details-marker { display: none; }
details.adv > summary::before { content: '▸ '; color: var(--t3); }
details.adv[open] > summary::before { content: '▾ '; }
.orient-pills {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px;
  margin-top: 8px;
}
.orient-pills label {
  display: block;
  text-align: center;
  padding: 7px 6px;
  border-radius: 6px;
  border: 1px solid var(--b1);
  background: var(--s3);
  color: var(--t2);
  font-size: 11.5px;
  cursor: pointer;
}
.orient-pills input { position: absolute; opacity: 0; pointer-events: none; }
.orient-pills input:checked + label {
  border-color: rgba(255,107,0,0.45);
  color: var(--accent);
  background: var(--accent-soft);
}

/* Pattern cards */
.pattern-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.pattern-card {
  display: flex; flex-direction: column; gap: 6px; align-items: center;
  background: var(--s3); border: 1px solid var(--b1); border-radius: 8px;
  padding: 8px; cursor: pointer; color: var(--t2); font-size: 11px;
}
.pattern-card:hover { border-color: var(--accent); color: var(--t1); }
.pattern-card canvas { width: 100%; border-radius: 4px; background: #111; }
.drop.drag { border-color: var(--accent); background: var(--accent-soft); }
body.is-rebuilding .canvas-meta .dot { background: var(--warning); }
.filename { font-size: 11px; color: var(--t2); margin-top: 6px; word-break: break-all; }
.source-actions { display: flex; gap: 6px; margin-top: 8px; }
.img-tools { display: flex; gap: 4px; margin-top: 8px; }
.icon-btn {
  width: 32px; height: 28px; border-radius: 6px; border: 1px solid var(--b1);
  background: var(--s3); color: var(--t2); cursor: pointer;
}
.icon-btn:hover:not(:disabled) { color: var(--t1); border-color: var(--b2); }
.icon-btn:disabled { opacity: 0.35; cursor: default; }
.bg-color { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.swatch { width: 18px; height: 18px; border-radius: 4px; border: 1px solid var(--b2); background: #fff; }
.swatch-label { font-family: var(--mono); font-size: 11px; color: var(--t2); }