body, html {
  margin: 0;
  background: -webkit-radial-gradient(center, ellipse cover, #000000 10%, #000000 90%);
}

canvas {
  display: block;
  cursor: crosshair;
}

h2 {
  position: absolute;
  bottom: 10px;
  width: 100%;
  letter-spacing: 4px;
  text-align: center;
  font-weight: bold;
  font-size: 1em;
  font-family: Helvetica;
  color: #ffffff;
}