style.css

/* from http://bl.ocks.org/mbostock/3310560#index.html */
body {
  font: 10px sans-serif;
}

.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

.bar {
  fill: steelblue;
}

.x.axis path {
  display: none;
}

/* from http://bl.ocks.org/mbostock/2706022#index.html */
.link {
  fill: none;
  stroke: #666;
  stroke-width: 1.5px;
}

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

text {
  font: 10px sans-serif;
  pointer-events: none;
}

/* Stuff I'm adding */
body { font-size: 14px; font-family: "Helvetica Neue" }
header h1 { font-size: 64px; font-weight: normal; margin-right: 12px; display: inline; }
header h2 { font-size: 120%; font-weight: normal; display: inline; }
header { border-bottom: 1px solid #cccccc; }
section h1 { font-weight: normal; display: inline-block; margin-right: 12px; }
div > * { font-size: 10px; }