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

canvas {
  display: block;
  width: 100%;
  height: 100%;
  image-rendering: -moz-crisp-edges;
  image-rendering: -webkit-crisp-edges;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  touch-action: none;
}

.toolbar {
  position: fixed;
  top: 10px;
  right: 10px;
  display: flex;
  flex-direction: column;
}

.tool {
  display: block;
  width: 3.5em;
  height: 3.5em;
  margin-bottom: 0.1em;
}