/* Reset & base */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: #f0f2f5;
  color: #333;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 20px;
}
#container {
  background: #fff;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
  max-width: 800px;
  width: 100%;
  padding: 20px;
}

h1 {
  margin-bottom: 16px;
}

/* Top controls */
#controls {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: flex-end;
  margin-bottom: 16px;
}
#controls label {
  display: flex;
  flex-direction: column;
  font-size: 0.9rem;
}
#controls input {
  margin-top: 4px;
  width: 80px;
  padding: 6px 8px;
  border: 1px solid #ccc;
  border-radius: 4px;
}
#controls button {
  padding: 8px 16px;
  background: #0069d9;
  color: #fff;
  border: none;
  border-radius: 4px;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.2s;
}
#controls button:hover { background: #0053a6; }
#controls button:active { background: #004085; }

/* Movement controls */
#movementControls {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}
#movementControls .row {
  display: flex;
  gap: 2px;
}
#movementControls button {
  width: 32px;
  height: 32px;
  padding: 4px;
  font-size: 0.8rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Rotate button */
#rotateBtn {
  background: #28a745;
}
#rotateBtn:hover { background: #218838; }
#rotateBtn:active { background: #1e7e34; }

/* Clear button */
#clearBtn {
  background: #dc3545;
}
#clearBtn:hover { background: #c82333; }
#clearBtn:active { background: #bd2130; }

/* Invert button */
#invertBtn {
  background: #6f42c1;
}
#invertBtn:hover { background: #5a32a3; }
#invertBtn:active { background: #4e2a8e; }

/* Undo/Redo buttons */
#undoBtn, #redoBtn {
  background: #6c757d;
}
#undoBtn:hover, #redoBtn:hover { background: #5a6268; }
#undoBtn:active, #redoBtn:active { background: #545b62; }
#undoBtn:disabled, #redoBtn:disabled {
  background: #c8ced3;
  cursor: not-allowed;
}

/* Tool controls */
#toolControls {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
  flex-wrap: wrap;
  align-items: center;
}

#toolControls button {
  padding: 8px 16px;
  background: #17a2b8;
  color: #fff;
  border: none;
  border-radius: 4px;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.2s;
}
#toolControls button:hover { background: #138496; }
#toolControls button:active { background: #117a8b; }
#toolControls button.active {
  background: #0069d9;
  box-shadow: inset 0 2px 4px rgba(0,0,0,0.3);
}

/* Zoom controls */
#zoomControls {
  display: flex;
  gap: 8px;
  align-items: center;
}

#zoomControls button {
  width: 32px;
  height: 32px;
  padding: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
}

#zoomValue {
  font-size: 0.9rem;
  min-width: 60px;
  text-align: center;
}

/* Drawing mode indicator */
#modeIndicator {
  padding: 6px 12px;
  border-radius: 4px;
  font-size: 0.9rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 6px;
}

#modeIndicator.drawing {
  background: #d4edda;
  color: #155724;
}

#modeIndicator.erasing {
  background: #f8d7da;
  color: #721c24;
}

#modeIndicator.filling {
  background: #d1ecf1;
  color: #0c5460;
}

/* Canvas */
#canvas {
  display: block;
  border: 1px solid #ccc;
  border-radius: 4px;
  background: #fff;
  cursor: crosshair;
  margin: 0 auto 12px;
  touch-action: none;
}

#canvas.fill-mode {
  cursor: pointer;
}

/* wrap the canvas so it scrolls */
#canvasWrapper {
  width: 100%;
  overflow: auto;
  border: 1px solid #ccc;
  border-radius: 4px;
  margin-bottom: 12px;
  max-height: 600px;
}
#canvasWrapper canvas {
  display: block;
}

/* Base64 controls under canvas */
#base64Controls {
  display: flex;
  gap: 12px;
  justify-content: center;
  margin-bottom: 12px;
  flex-wrap: wrap;
}
#base64Controls button {
  padding: 6px 12px;
  background: #0069d9;
  color: #fff;
  border: none;
  border-radius: 4px;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background 0.2s;
}
#base64Controls button:hover { background: #0053a6; }
#base64Controls button:active { background: #004085; }

/* Export extra controls */
#exportBtn {
  background: #28a745;
}
#exportBtn:hover { background: #218838; }
#exportBtn:active { background: #1e7e34; }

#downloadBtn {
  background: #17a2b8;
}
#downloadBtn:hover { background: #138496; }
#downloadBtn:active { background: #117a8b; }

#copyBtn {
  background: #6f42c1;
}
#copyBtn:hover { background: #5a32a3; }
#copyBtn:active { background: #4e2a8e; }

#exportPNGBtn {
  background: #fd7e14;
}
#exportPNGBtn:hover { background: #e86e0a; }
#exportPNGBtn:active { background: #d56408; }

/* Preset templates */
#presetControls {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
  flex-wrap: wrap;
  align-items: center;
}

#presetControls button {
  padding: 6px 12px;
  background: #6c757d;
  color: #fff;
  border: none;
  border-radius: 4px;
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.2s;
}
#presetControls button:hover { background: #5a6268; }
#presetControls button:active { background: #545b62; }

#presetControls label {
  font-size: 0.9rem;
  font-weight: 500;
  margin-right: 4px;
}

/* Output textarea */
#output {
  width: 100%;
  height: 100px;
  padding: 8px;
  font-family: monospace;
  font-size: 0.9rem;
  border: 1px solid #ccc;
  border-radius: 4px;
  resize: vertical;
}

/* Keyboard shortcuts help */
#keyboardHelp {
  margin-top: 16px;
  padding: 12px;
  background: #f8f9fa;
  border-radius: 4px;
  font-size: 0.85rem;
}

#keyboardHelp h3 {
  margin-bottom: 8px;
  font-size: 0.95rem;
}

#keyboardHelp ul {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 4px;
}

#keyboardHelp kbd {
  background: #fff;
  border: 1px solid #ccc;
  border-radius: 3px;
  padding: 2px 6px;
  font-family: monospace;
  font-size: 0.8rem;
}

/* Toggle switch for grid */
.toggle-switch {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
}

.toggle-switch input[type="checkbox"] {
  width: 40px;
  height: 20px;
  position: relative;
  cursor: pointer;
  appearance: none;
  background: #ccc;
  border-radius: 10px;
  transition: background 0.2s;
}

.toggle-switch input[type="checkbox"]:checked {
  background: #28a745;
}

.toggle-switch input[type="checkbox"]::before {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  top: 2px;
  left: 2px;
  background: white;
  transition: transform 0.2s;
}

.toggle-switch input[type="checkbox"]:checked::before {
  transform: translateX(20px);
}