java - GWTのdecoratedPopupPanelに別の背景色を適用するには?

Question

final DecoratedPopupPanel infoPopup = new DecoratedPopupPanel(true);
    infoPopup.setWidget(new Label("Table below displays the total number of users for each application for the selected time range."));
    infoPopup.setWidth("150px");

    inImage.addMouseOverHandler(new MouseOverHandler(){
        public void onMouseOver(MouseOverEvent arg0){
            int left = inImage.getAbsoluteLeft() + 10;
            int top = inImage.getAbsoluteTop() + 10;
           infoPopup.setPopupPosition(left, top);

            // Show the popup
            infoPopup.show();
        }

    });

    inImage.addMouseOutHandler(new MouseOutHandler(){
        public void onMouseOut(MouseOutEvent arg0){
           //hide
            infoPopup.hide();

        }
    });