title: Remove shadow/background glow on highcharts data label?
body: <p>If you check out my <a href="http://jsfiddle.net/WOUNDEDStevenJones/oe1vcmqj/1/" rel="noreferrer">http://jsfiddle.net/WOUNDEDStevenJones/oe1vcmqj/1/</a>, the red labels on the chart have a subtle white glow behind them (in at least Chrome and FF).  How do I remove that white glow?  Or worst case at least change the color to the same blue so it blends in?</p>
  
  <p>I've tried using <code>shadow</code>, <code>backgroundColor</code>, and other properties from their API (<a href="http://api.highcharts.com/highcharts#plotOptions.column.dataLabels" rel="noreferrer">http://api.highcharts.com/highcharts#plotOptions.column.dataLabels</a>), but can't figure out what is defining that glow behind the red text. </p>
  
  <pre><code>plotOptions: {
          columnrange: {
              dataLabels: {
                  enabled: true,
                  color: 'red',
                  inside: false,
                  xHigh: -45,
                  xLow: -9999999,
                  shadow: "#ff0000",
                  formatter: function () {
                      if (this.point.high) {
                          var myDate = new Date(this.y);
                          var newDateMs = Date.UTC(myDate.getUTCFullYear(),myDate.getUTCMonth(),myDate.getUTCDate());
                          return '&lt;b&gt;' + Highcharts.dateFormat('%m/%e',newDateMs) + '&lt;/b&gt;';
                      } else {
                          return null;
                      }
                  }
              }
          }
      }
  </code></pre>