$("div[widgetname='LABEL0']").find("pre").css("color","red")
或者$("div[widgetname=LABEL0] pre").css("color","red")
$(".fr-label.fr-widget-click").css("color","red")
或
$(".fr-label").css("color","red")
$("div[widgetname='LABEL0']").find("td").css("color","red")