:root {
  color-scheme: light;
  --background: #f5f7fa;
  --surface: #ffffff;
  --text: #182638;
  --muted: #536174;
  --accent: #a6192e;
  --border: #d5dce5;
  --control: #ffffff;
  --hover: #edf0f5;
  --selected: #fceef1;
  --danger: #b00020;
  --canvas: #e8edf3;
  --cell-input: #ddddff;
  --cell-filter: #ffdddd;
  --cell-output: #ddffdd;
  --cell-padding: #dddddd;
  --input-highlight: #0000aa;
  --filter-highlight: #aa0000;
  --output-highlight: #008000;
  scrollbar-color: var(--muted) var(--background);
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --background: #0f1722;
  --surface: #172333;
  --text: #e5edf6;
  --muted: #adbed0;
  --accent: #ff9bad;
  --border: #3b4b60;
  --control: #111d2b;
  --hover: #243549;
  --selected: #402535;
  --danger: #ff9bad;
  --canvas: #101820;
  --cell-input: #253c62;
  --cell-filter: #57343f;
  --cell-output: #214b3b;
  --cell-padding: #283442;
  --input-highlight: #8fbaff;
  --filter-highlight: #ff99a8;
  --output-highlight: #78e6a1;
}
[data-theme-toggle] {
  width: auto;
  flex: none;
  padding: 7px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--control);
  color: var(--text);
  font: inherit;
  font-size: 13px;
  cursor: pointer;
}
[data-theme-toggle]:hover { background: var(--hover); }
[data-theme-toggle]:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }
@media (forced-colors: active) { :root { scrollbar-color: auto; } }