html, body {
  margin: 0;
  padding: 0;
  font: 10px sans-serif;
}

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

rect:hover {
  opacity: 0.85
}

.x.axis path {
  display: none;
}

mean {
  stroke-opacity: 0.5;
}