graphic 虚线echarts 配置项内容和展示

请问如图的边框，有办法变成虚线么？多谢！

      option = {
    title: {
        text: 'Awesome Chart'
    },
    graphic: [{
            type: 'rect', 
            $action:'replace',
					invisible:false,
					id:'eTracelog',
					left:'5%',
					top:'5%',
					shape:{
						width:300,
						height:300
					},
					style:{
						fill:'#f8f8f8',
						stroke:'#60d0ff',
						lineWidth:3
					}
    }]
};