columnChart GridLines Style

<fx:Declarations>
        <!-- Background element array. -->
        <fx:Array id="bge">
            <mx:GridLines styleName="myStyle">
                <mx:horizontalStroke>
                    <mx:SolidColorStroke weight="3"/>
                </mx:horizontalStroke>
                <mx:verticalStroke>
                    <mx:SolidColorStroke weight="3"/>
                </mx:verticalStroke>
            </mx:GridLines>
        </fx:Array>
    </fx:Declarations>

  <fx:Style>
     .myStyle {
        gridDirection:"both";
        horizontalShowOrigin:true;
        horizontalTickAligned:false;
        horizontalChangeCount:1;
        verticalShowOrigin:false;
        verticalTickAligned:true;
        verticalChangeCount:1;
        horizontalFill:#990033;
        horizontalAlternateFill:#00CCFF;     
     } 
  </fx:Style>