svg {
    font: 10px sans-serif;
    }

    #chart {
    height: 1000px;
    background: #ddd;
    }

    text {
    pointer-events: none;
    }

    .grandparent text {
    font-weight: bold;
    }

    rect {
    fill: none;
    stroke: #fff;
    }

    rect.parent,
    .grandparent rect {
    stroke-width: 2px;
    }

    .grandparent rect {
    fill: #557A95;
    }

    .grandparent:hover rect {
    fill: #557A95;
    }

    .children rect.parent,
    .grandparent rect {
    cursor: pointer;
    }

    .children rect.parent {
    fill: #7395AE;
    fill-opacity: .5;
    }

    .children:hover rect.child {
    fill: #d3beda;
    fill-opacity: 1;    }