body {
  font-family: sans-serif;
  text-align: center;
  background: #fafafa;
  margin: 20px;
}

#canvas-container {
  position: relative;
  display: inline-block;
  border: 2px solid #ccc;
  touch-action: none; /* prevent scrolling while drawing */
}

canvas {
  display: block;
  max-width: 100%;
  height: auto;
  background: white;
}

.controls {
  margin-top: 10px;
}