将D3 Piechart置于div的中心，并考虑其尺寸

<div id="chartContainer" style="width: 400px; height: 400px;"></div>

var container = d3.select("#chartContainer");
var width = container.style("width").replace("px", "");
var height = container.style("height").replace("px", "");
var radius = Math.min(width, height) / 2;

var svg = container.append("svg")
    .attr("width", width)
    .attr("height", height);

#chartContainer {
    display: flex;
    justify-content: center;
    align-items: center;
}

var data = [10, 20, 30, 40];

var color = d3.scaleOrdinal(d3.schemeCategory10);

var pie = d3.pie()
    .value(function(d) { return d; });

var arc = d3.arc()
    .innerRadius(0)
    .outerRadius(radius);

var arcs = svg.selectAll("arc")
    .data(pie(data))
    .enter()
    .append("g")
    .attr("class", "arc");

arcs.append("path")
    .attr("d", arc)
    .attr("fill", function(d) { return color(d.data); });