[docs] bars > keyWidth

<!DOCTYPE html>
<html>

<head>
  <meta charset="utf-8">
  <title>ZingSoft Demo</title>

  <script nonce="undefined" src="https://cdn.zingchart.com/zingchart.min.js"></script>
  <style>
    html,
    body,
    #myChart {
      height: 100%;
      width: 100%;
    }
  </style>
</head>

<body>
  <div id='myChart'></div>
  <script>
    ZC.LICENSE = ["569d52cefae586f634c54f86dc99e6a9", "b55b025e438fa8a98e32482b5f768ff5"];
    let chartConfig = {
      type: 'bar',
      plot: {
        keyWidth: true,
        barWidth: 0.3
      },
      series: [{
          values: [20, 40, 25]
        },
        {
          values: [5, 30, 21]
        },
        {
          values: [30, 5, 18]
        }
      ]
    };

    zingchart.render({
      id: 'myChart',
      data: chartConfig,
      height: '100%',
      width: '100%'
    });
  </script>
</body>

</html>

<!DOCTYPE html>
<html>

<head>
  <meta charset="utf-8">
  <title>ZingSoft Demo</title>

  <script src="https://cdn.zingchart.com/zingchart.min.js"></script>
</head>

<body>
  <div id='myChart'></div>
</body>

</html>

html,
body,
#myChart {
  height: 100%;
  width: 100%;
}

let chartConfig = {
  type: 'bar',
  plot: {
    keyWidth: true,
    barWidth: 0.3
  },
  series: [{
      values: [20, 40, 25]
    },
    {
      values: [5, 30, 21]
    },
    {
      values: [30, 5, 18]
    }
  ]
};

zingchart.render({
  id: 'myChart',
  data: chartConfig,
  height: '100%',
  width: '100%'
});