<script src="https://d3js.org/d3.v4.min.js"></script>
<style> /* set the CSS */

body { font: 12px Arial;}

path {
    stroke: steelblue;
    stroke-width: 2;
    fill: none;
}

.axis path,
.axis line {
    fill: none;
    stroke: grey;
    stroke-width: 1;
    shape-rendering: crispEdges;
}

</style>
<div id="viz"></div>
<script>

    var sampleSVG = d3.select("#viz")
        .append("svg")
        .attr("width", 100)
        .attr("height", 100);

    sampleSVG.append("circle")
        .style("stroke", "gray")
        .style("fill", "white")
        .attr("r", 40)
        .attr("cx", 50)
        .attr("cy", 50)
        .on("mouseover", function(){d3.select(this).style("fill", "aliceblue");})
        .on("mouseout", function(){d3.select(this).style("fill", "white");});

</script>