Canvas concentric circles

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { background-color: #F5EFEB; margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
  <script>
    // Feel free to change or delete any of the code you see in this editor!
    var canvas = d3.select("body").append("canvas")
      .attr("width", 960)
      .attr("height", 500);
    var context = canvas.node().getContext('2d');

var total = 100;
    var turnout = 68;
    
    var x = d3.scaleLinear().range([0,100]).domain([0,100]);
    
    context.fillStyle = '#ddd'
    context.beginPath();
    context.arc(100, 100, x(total), 0, 2 * Math.PI, true);
    context.fill();
    context.closePath();
    context.fillStyle = '#383838';
    context.beginPath();
    context.arc(100, 100, x(turnout), 0, 2 * Math.PI, true);
    context.fill();
    context.closePath();
    context.strokeStyle = '#383838';
    context.lineWidth = 5;
    context.beginPath();
    context.moveTo(100, 100);
    context.lineTo(250, 100);
    context.stroke();
    
    context.font = '40pt Times';
    context.fillText('68,4%', 250, 100);
    </script>

</script>
</body>

https://d3js.org/d3.v4.min.js