triple dial gauge chart readability issue

<!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 {
      height: 100%;
      width: 100%;
      margin: 0;
      padding: 0;
    }

    #myChart {
      height: 100%;
      width: 100%;
      min-height: 150px;
    }

    .zc-ref {
      display: none;
    }
  </style>
</head>

<body>
  <div id="myChart"><a class="zc-ref" href="https://www.zingchart.com">Powered by ZingChart</a></div>
  <script>
    ZC.LICENSE = ["569d52cefae586f634c54f86dc99e6a9", "b55b025e438fa8a98e32482b5f768ff5"];
    var myConfig1 = {
      "type": "gauge",
      legend: {
        text: '%t %v',
        width: 120
      },
      "scale-r": {
        "aperture": 200, //Specify your scale range.
        "values": "0:100:20" //Provide min/max/step scale values.
      },
      tooltip: {
        text: '%t'
      },
      plot: {
        valueBox: {
          _placement: 'out',
          text: '%v%',
          fontSize: 10,
          "padding-left": 40
        }
      },
      "series": [{
          "values": [35]
        },
        {
          "values": [40]
        },
        {
          "values": [25]
        },
      ]
    };


    zingchart.render({
      id: 'myChart',
      data: myConfig1,
      height: 350,
      width: 350
    });
  </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"><a class="zc-ref" href="https://www.zingchart.com">Powered by ZingChart</a></div>
</body>

</html>

html,
body {
  height: 100%;
  width: 100%;
  margin: 0;
  padding: 0;
}

#myChart {
  height: 100%;
  width: 100%;
  min-height: 150px;
}

.zc-ref {
  display: none;
}

var myConfig1 = {
  "type": "gauge",
  legend: {
    text: '%t %v',
    width: 120
  },
  "scale-r": {
    "aperture": 200, //Specify your scale range.
    "values": "0:100:20" //Provide min/max/step scale values.
  },
  tooltip: {
    text: '%t'
  },
  plot: {
    valueBox: {
      _placement: 'out',
      text: '%v%',
      fontSize: 10,
      "padding-left": 40
    }
  },
  "series": [{
      "values": [35]
    },
    {
      "values": [40]
    },
    {
      "values": [25]
    },
  ]
};


zingchart.render({
  id: 'myChart',
  data: myConfig1,
  height: 350,
  width: 350
});