header {
  height: 150px;
  padding: 10px;
  text-align: center;
}
#section {
  margin: auto;
  width: 1000px;
  font-family: 'PT Sans', sans-serif;
}
footer {
  clear:both;
  padding:20px;
  text-align:center;
  font-family: 'PT Sans', sans-serif;
}
.banner {
  color: #000;
  font-size: 72px;
  font-weight: 200;
  text-decoration: none;
  font-family: 'Raleway', sans-serif;
}
a.banner:hover {
  text-decoration: underline;
}
.explanation {
  color: #000;
  font-size: 22px;
  font-weight: 200;
  text-decoration: none;
  font-family: 'Raleway', sans-serif;
}
.y.axis path {
  display: none;
}

.y.axis line {
  stroke: #fff;
  stroke-opacity: .2;
  shape-rendering: crispEdges;
}

.y.axis .zero line {
  stroke: #000;
  stroke-opacity: 1;
}