body {
    margin: 0;
    padding: 0;
}

.node circle {
  fill: #fff;
  stroke: steelblue;
  stroke-width: 1.5px;
}

.node {
  cursor: pointer;
  font: 10px sans-serif;
}

.link {
  fill: none;
  stroke: #ccc;
  stroke-width: 1.5px;
}

.zoom {
    position: fixed;
    top: 5px;
    right: 5px;
}