.chart {
 display: block;
 margin: auto;
     margin-top: 10px;
     font-size: 1em;
 }

rect {
stroke: #eee;
fill: #aaa;
    fill-opacity: .8;
}

rect.parent {
cursor: pointer;
fill: steelblue;
}

text {
    pointer-events: none;
}