/* Web fonts were removed from the blocking CSS path so the canvases initialise reliably on slow/mobile networks. */

  :root {
    --bg:       #f7f4ef;
    --surface:  #ffffff;
    --border:   #d8d0c4;
    --text:     #1a1612;
    --muted:    #7a6f65;
    --accent:   #3d6b4f;
    --accent2:  #8b3a2a;
    --shadow:   0 2px 12px rgba(0,0,0,0.08);
  }

  *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

  body {
    background: var(--bg);
    color: var(--text);
    font-family: 'EB Garamond', Georgia, serif;
    font-size: 17px;
    line-height: 1.6;
    min-height: 100vh;
  }

  header {
    background: var(--text);
    color: var(--bg);
    padding: 22px 36px;
    display: flex;
    align-items: baseline;
    gap: 18px;
    border-bottom: 3px solid var(--accent);
  }
  header h1 {
    font-size: 1.7rem;
    font-weight: 500;
    letter-spacing: 0.01em;
  }
  header span {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    color: #9a9080;
    letter-spacing: 0.05em;
  }
  header span a,
  header span a:visited {
    color: #f2e8d8;
    text-decoration: none;
  }
  header span a:hover,
  header span a:focus {
    color: #fffaf0;
    text-decoration: underline;
  }

  .layout {
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: 28px;
    max-width: 1100px;
    margin: 32px auto;
    padding: 0 28px;
  }

  @media (max-width: 780px) {
    .layout { grid-template-columns: 1fr; }
  }

  /* ── canvas panel ── */
  .canvas-panel {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 4px;
    box-shadow: var(--shadow);
    overflow: hidden;
  }
  .canvas-panel header.panel-title {
    background: transparent;
    border-bottom: 1px solid var(--border);
    border-top: none;
    padding: 10px 16px;
    font-size: 0.78rem;
    font-family: 'JetBrains Mono', monospace;
    letter-spacing: 0.08em;
    color: var(--muted);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 14px;
    flex-wrap: wrap;
  }
  .panel-title-text {
    color: var(--muted);
    flex-shrink: 0;
    text-transform: uppercase;
  }
  .canvas-toolbar {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 12px;
    flex-wrap: wrap;
    margin-left: auto;
  }
  .shape-indicator {
    color: var(--text);
    white-space: nowrap;
  }
  #shape-badge { color: var(--text); }
  .canvas-size-inline {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding-left: 12px;
    border-left: 1px solid var(--border);
    color: var(--muted);
    white-space: nowrap;
  }
  .canvas-size-inline label {
    display: inline-flex;
    align-items: center;
    gap: 4px;
  }
  .canvas-size-inline label span,
  .dimension-times {
    color: var(--muted);
  }
  .canvas-size-inline input[type=number] {
    width: 46px;
    padding: 2px 5px;
    border: 1px solid var(--border);
    border-radius: 3px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    background: var(--bg);
    color: var(--text);
    text-align: center;
  }
  .canvas-size-inline input[type=number]:focus {
    outline: 2px solid var(--accent);
    border-color: var(--accent);
  }

  @media (max-width: 780px) {
    .canvas-panel header.panel-title { align-items: flex-start; }
    .canvas-toolbar {
      width: 100%;
      justify-content: space-between;
      margin-left: 0;
    }
    .canvas-size-inline {
      padding-left: 0;
      border-left: none;
    }
  }

  #canvas-wrap {
    padding: 16px;
  }
  @media (max-width: 780px) {
    #canvas-wrap { padding: 12px; }
  }
  canvas {
    display: block;
    width: 100% !important;
    height: auto !important;
    cursor: crosshair;
    border-radius: 2px;
    background: #fffdf8;
  }

  /* ── right column ── */
  .side { display: flex; flex-direction: column; gap: 18px; }

  /* drag-and-drop */
  .card {
    transition: box-shadow 0.15s, opacity 0.15s, transform 0.15s;
  }
  .card.dragging {
    opacity: 0.35;
    box-shadow: 0 8px 32px rgba(0,0,0,0.18);
  }
  .card.drag-over {
    box-shadow: 0 0 0 2px var(--accent), var(--shadow);
  }
  .drag-handle {
    cursor: grab;
    padding: 0 6px 0 0;
    color: var(--border);
    font-size: 0.9rem;
    letter-spacing: -1px;
    line-height: 1;
    flex-shrink: 0;
    transition: color 0.15s;
    touch-action: none;
    user-select: none;
    -webkit-user-select: none;
  }
  .drag-handle:hover { color: var(--muted); }
  .drag-handle:active { cursor: grabbing; }
  body.card-dragging * { cursor: grabbing !important; }
  @media (max-width: 780px) {
    body.card-dragging {
      overflow: hidden;
      overscroll-behavior: none;
    }
  }
  @media (pointer: coarse) {
    .drag-handle {
      padding: 8px 10px 8px 0;
      margin: -8px 0;
      min-width: 28px;
      text-align: center;
    }
  }
  .card-head-label { flex: 1; }
  .card-title-tools {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-left: auto;
    margin-right: 7px;
    flex-shrink: 0;
  }
  .card-stale-badge {
    display: none;
    border: 1px solid color-mix(in srgb, var(--accent2) 58%, var(--border));
    border-radius: 3px;
    color: var(--accent2);
    padding: 1px 4px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.62rem;
    letter-spacing: 0;
    line-height: 1.25;
    text-transform: lowercase;
  }
  .card.is-stale .card-stale-badge { display: inline-flex; }
  .card-pin-btn {
    border: 1px solid transparent;
    background: transparent;
    color: var(--muted);
    border-radius: 3px;
    width: 22px;
    height: 18px;
    min-width: 22px;
    min-height: 18px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 0;
    line-height: 1;
    padding: 0;
    touch-action: manipulation;
    -webkit-tap-highlight-color: transparent;
    flex: 0 0 auto;
  }
  .card-pin-icon {
    width: 12px;
    height: 12px;
    display: block;
    fill: none;
    stroke: currentColor;
    stroke-width: 2.4;
    stroke-linecap: round;
    stroke-linejoin: round;
    pointer-events: none;
  }
  .card-pin-btn:hover,
  .card.is-pinned .card-pin-btn {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(61,107,79,0.08);
  }
  @media (max-width: 980px) {
    .card-pin-btn {
      display: none;
    }
  }
 
  .card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 4px;
    box-shadow: var(--shadow);
  }
  .card-head {
    padding: 9px 16px;
    border-bottom: 1px solid var(--border);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--muted);
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    user-select: none;
    transition: background 0.15s;
  }
  .card-head:hover { background: rgba(0,0,0,0.025); }
  .card-head .toggle-icon {
    font-style: normal;
    font-size: 0.9rem;
    color: var(--muted);
    transition: transform 0.22s ease;
    display: inline-block;
    line-height: 1;
  }
  .card.collapsed .card-head .toggle-icon { transform: rotate(-90deg); }
  .card.collapsed .card-head { border-bottom-color: transparent; }
  .card-body {
    padding: 14px 16px;
    overflow: hidden;
    transition: max-height 0.25s ease, opacity 0.2s ease, padding 0.2s ease;
    max-height: 1400px;
    opacity: 1;
  }
  .card.collapsed .card-body {
    max-height: 0;
    opacity: 0;
    padding-top: 0;
    padding-bottom: 0;
  }

  .stat-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding: 5px 0;
    border-bottom: 1px dotted var(--border);
    gap: 8px;
  }
  .stat-row:last-child { border-bottom: none; }
  .stat-label {
    font-size: 0.88rem;
    color: var(--muted);
    flex-shrink: 0;
  }
  .stat-value {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.82rem;
    color: var(--text);
    text-align: right;
    word-break: break-all;
  }

  /* semistandard input row */
  .ssrow {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 6px 0 2px;
    border-bottom: 1px dotted var(--border);
  }
  .ssrow label { font-size: 0.88rem; color: var(--muted); flex: 1; }
  .ssrow input[type=number] {
    width: 56px;
    padding: 3px 6px;
    border: 1px solid var(--border);
    border-radius: 3px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.82rem;
    background: var(--bg);
    color: var(--text);
    text-align: center;
  }
  .ssrow input[type=number]:focus { outline: 2px solid var(--accent); border-color: var(--accent); }

  /* options */
  .opt-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 5px 0;
    font-size: 0.9rem;
    cursor: pointer;
    user-select: none;
  }
  .opt-row input[type=checkbox] { accent-color: var(--accent); width: 15px; height: 15px; cursor: pointer; }

  /* extra: shape input */
  .input-method {
    margin-top: 8px;
  }
  .input-method + .input-method {
    margin-top: 14px;
    padding-top: 12px;
    border-top: 1px solid var(--border);
  }
  .input-label {
    display: block;
    margin-bottom: 4px;
    font-size: 0.78rem;
    font-family: 'JetBrains Mono', monospace;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.03em;
  }
  .input-row {
    display: flex;
    gap: 8px;
    margin-top: 4px;
  }
  .input-row input[type=text] {
    flex: 1;
    padding: 5px 10px;
    border: 1px solid var(--border);
    border-radius: 3px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.82rem;
    background: var(--bg);
    color: var(--text);
  }
  .input-row input[type=text]:focus { outline: 2px solid var(--accent); border-color: var(--accent); }
  .btn {
    padding: 5px 14px;
    border: 1px solid var(--accent);
    border-radius: 3px;
    background: var(--accent);
    color: #fff;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.78rem;
    cursor: pointer;
    letter-spacing: 0.04em;
    transition: background 0.15s, transform 0.1s;
  }
  .btn:hover { background: #2e5239; }
  .btn:active { transform: scale(0.97); }
  .btn-ghost {
    background: transparent;
    color: var(--accent2);
    border-color: var(--accent2);
  }
  .btn-ghost:hover { background: var(--accent2); color: #fff; }

  .hint {
    font-size: 0.78rem;
    color: var(--muted);
    margin-top: 5px;
    font-style: italic;
  }
  .complexity-preview,
  .result-meta,
  .limit-details {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.68rem;
    line-height: 1.45;
    color: var(--muted);
    border-top: 1px dotted var(--border);
    padding-top: 5px;
    margin-top: 6px;
    overflow-wrap: anywhere;
  }
  .limit-details summary {
    cursor: pointer;
    color: var(--accent);
  }
  .result-meta {
    font-style: normal;
  }

  /* conjugate / clear row */
  .action-row {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
  }

  /* export textarea */
  #export-out {
    width: 100%;
    height: 60px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 3px;
    background: var(--bg);
    padding: 6px 8px;
    resize: vertical;
    color: var(--text);
    margin-top: 6px;
  }

  footer {
    text-align: center;
    padding: 28px;
    font-size: 0.8rem;
    color: var(--muted);
    border-top: 1px solid var(--border);
    margin-top: 20px;
  }
  footer a { color: var(--accent); text-decoration: none; }

  /* error flash */
  .err { color: var(--accent2); font-size: 0.8rem; margin-top: 4px; font-style: italic; }


  /* Lie algebra decomposition rows */
  .lie-subsection {
    margin-top: 12px;
    padding-top: 10px;
    border-top: 1px dotted var(--border);
  }
  .lie-subsection-title {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 3px;
  }
  .decomp-scroll {
    display: flex;
    flex-direction: column;
    gap: 10px;
    max-height: min(320px, 48vh);
    min-height: 116px;
    overflow-y: auto;
    overflow-x: hidden;
    margin-top: 8px;
    background: var(--surface);
    padding: 0 10px 12px 0;
    box-sizing: border-box;
    overscroll-behavior: contain;
    scrollbar-gutter: stable;
    scrollbar-color: color-mix(in srgb, var(--accent) 68%, var(--surface)) var(--surface);
    scrollbar-width: thin;
    min-width: 0;
  }
  .decomp-scroll::-webkit-scrollbar {
    width: 10px;
    height: 10px;
  }
  .decomp-scroll::-webkit-scrollbar-track {
    background: var(--surface);
    border-left: 1px solid var(--border);
  }
  .decomp-scroll::-webkit-scrollbar-thumb {
    background: color-mix(in srgb, var(--accent) 68%, var(--surface));
    border: 2px solid var(--surface);
    border-radius: 999px;
  }
  .decomp-scroll::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
  }
  .decomp-scroll > .hint {
    display: block;
    padding: 2px 0 4px;
  }
  .branching-scroll {
    overflow-x: auto;
    padding-right: 10px;
  }
  .branching-rule-row {
    margin-bottom: 12px;
  }
  .branching-action-row {
    margin-bottom: 10px;
  }
  .decomp-row {
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 0;
    padding: 3px 0;
    border-bottom: 1px dotted var(--border);
  }
  .decomp-row:last-child { border-bottom: none; }
  .decomp-mult {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.78rem;
    color: var(--accent);
    min-width: 24px;
    text-align: right;
    white-space: nowrap;
    flex-shrink: 0;
  }
  .decomp-diagram {
    display: inline-flex;
    align-items: center;
    min-width: 20px;
    max-width: 112px;
    flex-shrink: 0;
    overflow: hidden;
  }
  .decomp-diagram svg {
    display: block;
    max-width: 112px;
    height: auto;
  }
  .decomp-label {
    min-width: 0;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    color: var(--muted);
    line-height: 1.25;
    word-break: break-word;
    overflow-wrap: anywhere;
  }
  .decomp-label .decomp-dyn {
    color: var(--text);
  }
  .decomp-label .decomp-orbit {
    color: var(--muted);
    white-space: nowrap;
  }

  @media (max-width: 780px) {
    .decomp-scroll {
      padding: 0 8px 10px 0;
    }
    .decomp-row {
      gap: 8px;
      padding: 3px 0;
    }
    .decomp-diagram,
    .decomp-diagram svg {
      max-width: 96px;
    }
  }

  /* symmetric-function expansions */
  .symfun-control-row {
    display: grid;
    grid-template-columns: minmax(46px, max-content) minmax(0, 1fr);
    align-items: center;
    column-gap: 10px;
    padding: 0;
    margin-bottom: 0;
  }
  .symfun-n-row {
    padding-bottom: 5px;
  }
  .symfun-basis-row {
    padding-bottom: 7px;
    margin-bottom: 2px;
    border-bottom: 1px dotted var(--border);
  }
  .symfun-control-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    color: var(--muted);
    min-width: 46px;
  }
  .symfun-variable-controls {
    display: flex;
    align-items: center;
    gap: 8px;
    justify-content: flex-start;
    flex-wrap: wrap;
    min-width: 0;
  }
  .symfun-control-row input[type=number],
  .symfun-control-row input[type=text] {
    width: 68px;
    padding: 3px 6px;
    border: 1px solid var(--border);
    border-radius: 3px;
    background: var(--bg);
    color: var(--text);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.74rem;
    text-align: center;
  }
  .symfun-control-row input[type=text][readonly] {
    color: var(--muted);
    background: color-mix(in srgb, var(--bg) 72%, var(--surface));
  }
  .symfun-control-row input[type=number]:focus,
  .symfun-control-row input[type=text]:focus {
    outline: 2px solid var(--accent);
    border-color: var(--accent);
  }
  .symfun-infinite-toggle {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    color: var(--muted);
    cursor: pointer;
    user-select: none;
  }
  .symfun-infinite-toggle input[type=checkbox] {
    width: 14px;
    height: 14px;
    accent-color: var(--accent);
    cursor: pointer;
  }
  .symfun-basis-select {
    border: 1px solid var(--border);
    border-radius: 3px;
    background: var(--bg);
    color: var(--text);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    padding: 2px 5px;
    min-width: 64px;
  }
  .symfun-basis-select:disabled {
    opacity: 0.42;
    cursor: not-allowed;
  }
  .symfun-basis-controls {
    justify-content: flex-start;
    flex-wrap: nowrap;
  }
  .symfun-basis-select:focus {
    outline: 2px solid var(--accent);
    border-color: var(--accent);
  }
  .symfun-inline-select {
    border: 1px solid var(--border);
    border-radius: 3px;
    background: var(--bg);
    color: var(--text);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    padding: 1px 5px;
    max-width: 74px;
  }
  .symfun-omega-label {
    display: inline-flex;
    align-items: baseline;
    gap: 2px;
  }
  .symfun-omega-row {
    grid-template-columns: minmax(108px, max-content) minmax(0, 1fr);
    padding-top: 7px;
  }
  .symfun-export-btn {
    border: 1px solid var(--accent);
    border-radius: 3px;
    background: transparent;
    color: var(--accent);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    padding: 2px 7px;
    cursor: pointer;
    margin-left: auto;
  }
  .symfun-export-btn:hover {
    background: rgba(61,107,79,0.08);
  }
  .symfun-expansions {
    max-height: min(460px, 58vh);
    overflow: auto;
    padding: 0 8px 6px 0;
    scrollbar-gutter: stable;
    scrollbar-color: color-mix(in srgb, var(--accent) 68%, var(--surface)) var(--surface);
    scrollbar-width: thin;
  }
  .symfun-expansions::-webkit-scrollbar {
    width: 10px;
    height: 10px;
  }
  .symfun-expansions::-webkit-scrollbar-track {
    background: var(--surface);
    border-left: 1px solid var(--border);
  }
  .symfun-expansions::-webkit-scrollbar-thumb {
    background: color-mix(in srgb, var(--accent) 68%, var(--surface));
    border: 2px solid var(--surface);
    border-radius: 999px;
  }
  .symfun-expansions::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
  }
  .symfun-row {
    display: grid;
    grid-template-columns: minmax(46px, max-content) minmax(0, 1fr);
    align-items: start;
    column-gap: 10px;
    padding: 4px 0;
    border-bottom: 1px dotted var(--border);
    font-size: 0.82rem;
    line-height: 1.5;
  }
  .symfun-row:last-child {
    border-bottom: none;
  }
  .symfun-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.74rem;
    color: var(--muted);
    min-width: 46px;
    white-space: nowrap;
  }
  .symfun-label sub,
  .symfun-symbol sub {
    font-size: 0.72em;
  }
  .symfun-value {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    line-height: 1.45;
    color: var(--text);
    overflow-wrap: anywhere;
    min-width: 0;
  }
  .symfun-symbol {
    color: var(--text);
    font-weight: 500;
    white-space: nowrap;
  }
  .symfun-coeff {
    color: var(--accent2);
  }
  .symfun-too-large {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.74rem;
    color: var(--accent2);
    line-height: 1.45;
  }

  .tooltip-label {
    cursor: help;
    text-decoration: underline dotted rgba(122,111,101,0.55);
    text-underline-offset: 2px;
  }

  .custom-tooltip {
    position: fixed;
    z-index: 10000;
    max-width: min(320px, calc(100vw - 24px));
    padding: 7px 9px;
    border: 1px solid var(--border);
    border-radius: 4px;
    background: var(--surface);
    color: var(--text);
    box-shadow: 0 6px 22px rgba(0,0,0,0.16);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    line-height: 1.45;
    letter-spacing: 0;
    text-transform: none;
    pointer-events: none;
    opacity: 0;
    transform: translateY(3px);
    transition: opacity 0.12s ease, transform 0.12s ease;
  }

  .custom-tooltip.visible {
    opacity: 1;
    transform: translateY(0);
  }