body {
  margin: 0;

}

canvas {
  width: 100%;
  height: 100%;
}

#divLegend {
  position: absolute;
  pointer-events: none; /*pass mouse events to parent*/
  background: rgba(255,255,255,0.5);
  box-shadow: 0 0 2px #bbb;
  top: 20px;
  right: 10px;
  opacity: 1;
  z-index: 1;
  font-size: small;
}