:root {
  --color-empty: #ffffff;
  --color-wall: #2b2d42;
  --color-start: #2a9d8f;
  --color-finish: #e63946;
  --color-path: #f4a261;
  --color-grid-line: #d3d6dc;
  --color-page-background: #f4f5f7;
  --color-surface: #ffffff;
  --color-border: #d3d6dc;
  --color-text: #1f2430;
  --color-text-muted: #5b6270;
  --color-button-background: #ffffff;
  --color-button-hover: #e9ebef;
  --color-button-pressed-background: #2b2d42;
  --color-button-pressed-text: #ffffff;
  --color-focus-ring: #3a86ff;

  --cell-size: 4px;
  --space: 12px;
  --sidebar-width: 200px;
  --workspace-gap: 24px;

  color-scheme: light;
}

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

html,
body {
  height: 100%;
  margin: 0;
}

body {
  background: var(--color-page-background);
  color: var(--color-text);
  font: 14px/1.4 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  overflow: hidden;
}

.app {
  display: flex;
  flex-direction: column;
  height: 100%;
  padding: var(--space);
  gap: var(--space);
}

.header {
  display: flex;
  align-items: center;
  gap: calc(var(--space) * 2);
  min-height: 36px;
}

.title {
  margin: 0;
  font-size: 18px;
  font-weight: 600;
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: calc(var(--space) * 2);
}

.toolbar-group {
  display: flex;
  gap: 6px;
}

.tool {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 32px;
  padding: 0 12px;
  background: var(--color-button-background);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font: inherit;
  cursor: pointer;
}

.tool:hover {
  background: var(--color-button-hover);
}

.tool:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

.tool[aria-pressed="true"] {
  background: var(--color-button-pressed-background);
  border-color: var(--color-button-pressed-background);
  color: var(--color-button-pressed-text);
}

.shortcut {
  font: 11px/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  opacity: 0.7;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.workspace {
  display: flex;
  flex: 1;
  min-height: 0;
  justify-content: center;
  align-items: flex-start;
  gap: var(--workspace-gap);
  overflow: hidden;
}

.board {
  position: relative;
  flex: none;
  width: calc(var(--grid-size) * var(--cell-size) + var(--grid-line-width));
  height: calc(var(--grid-size) * var(--cell-size) + var(--grid-line-width));
}

.board-canvas {
  position: absolute;
  top: 0;
  left: 0;
  display: block;
  width: calc(var(--grid-size) * var(--cell-size));
  height: calc(var(--grid-size) * var(--cell-size));
  image-rendering: crisp-edges;
  image-rendering: pixelated;
  touch-action: none;
}

.board-lines {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--color-grid-line) var(--grid-line-width), transparent var(--grid-line-width)),
    linear-gradient(to bottom, var(--color-grid-line) var(--grid-line-width), transparent var(--grid-line-width));
  background-size: var(--cell-size) var(--cell-size);
}

.sidebar {
  display: flex;
  flex: none;
  flex-direction: column;
  gap: calc(var(--space) * 2);
  width: var(--sidebar-width);
}

.status {
  margin: 0;
  padding: 8px 10px;
  min-height: 2.6em;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 4px;
}

.legend-title {
  margin: 0 0 8px;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.legend-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.swatch {
  width: 16px;
  height: 16px;
  border: 1px solid var(--color-grid-line);
}

.swatch-empty {
  background: var(--color-empty);
}

.swatch-wall {
  background: var(--color-wall);
}

.swatch-start {
  background: var(--color-start);
}

.swatch-finish {
  background: var(--color-finish);
}

.swatch-path {
  background: var(--color-path);
}