path {
    fill: none;
    stroke: #111;
}
div.tooltip {
    color: #222;
    background: #fff;
    padding: .5em;
    text-shadow: #f5f5f5 0 1px 0;
    border-radius: 2px;
    box-shadow: 0px 0px 2px 0px #a6a6a6;
    opacity: 0.9;
    position: absolute;
}