Setting left and right margins on a Spark TextArea control in Flex 4

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/06/04/setting-left-and-right-margins-on-a-spark-textarea-control-in-flex-4/ -->
<s:Application name="Spark_TextArea_paragraphStartIndent_text"
        xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        xmlns:mx="library://ns.adobe.com/flex/halo">
    <s:layout>
        <s:VerticalLayout />
    </s:layout>
 
    <fx:Script>
        <![CDATA[
            private function sliderStart_change(evt:Event):void {
                textArea.setStyle("paragraphStartIndent", sliderStart.value);
            }
 
            private function sliderEnd_change(evt:Event):void {
                textArea.setStyle("paragraphEndIndent", sliderEnd.value);
            }
        ]]>
    </fx:Script>
 
    <mx:ApplicationControlBar width="100%" cornerRadius="0">
        <mx:Form styleName="plain">
            <mx:FormItem label="paragraphStartIndent:">
                <s:HSlider id="sliderStart"
                        liveDragging="true"
                        change="sliderStart_change(event);" />
            </mx:FormItem>
            <mx:FormItem label="paragraphEndIndent:">
                <s:HSlider id="sliderEnd"
                        liveDragging="true"
                        change="sliderEnd_change(event);" />
            </mx:FormItem>
        </mx:Form>
    </mx:ApplicationControlBar>
 
    <s:Group width="100%" height="100%">
        <s:TextArea id="textArea"
                textAlign="justify"
                left="10" right="10"
                top="10" bottom="10">
            <s:content>
                <fx:String source="lorem.html" />
            </s:content>
        </s:TextArea>
    </s:Group>
 
</s:Application>