adobe flash builder 4:css类型选择器在组件中不受支持spark.components.标签[复制]

可能重复:
Warning: css type selectors are not supported in components ‘sparks.component.TextInput’

<fx:Style>
    @namespace s "library://ns.adobe.com/flex/spark";
    @namespace mx "library://ns.adobe.com/flex/mx";
    @namespace local "*";
    s|Label {
        font-size:12;
        font-weight:bold;
        color:white;
    }
    #timeLeftHGroup {
        left:30;
        top:12;
    }

我收到以下警告 s|Label 线路:

CSS type selectors are not supported in components: 'spark.components.Label'    

好。。CSS代码确实有效!它确实改变了颜色,使文本加粗,并将字体大小改为12,那么为什么我会收到这个警告?