tooltip.css

/* CSS for tooltip box that appears when mouse hovers over D3.js map. */
path:hover {
    fill: #72716c;
}
#tooltip {
        position: absolute;
        width: 200px;
        height: auto;
        padding: 10px;
        background-color: white;
        -webkit-border-radius: 10px;
        -moz-border-radius: 10px;
        border-radius: 10px;
        -webkit-box-shadow: 4px 4px 10px rgba(0, 0, 0, 0.4);
        -moz-box-shadow: 4px 4px 10px rgba(0, 0, 0, 0.4);
        box-shadow: 4px 4px 10px rgba(0, 0, 0, 0.4);
        pointer-events: none;
        z-index: 3; /* Makes tooltip box appear above other elements on webpage. */
}
#tooltip.hidden {
        display: none;
}

#tooltip div.hidden{
     display: none;
}
#tooltip p {
        margin: 0;
        font-family: sans-serif;
        font-size: 16px;
        line-height: 20px;
}