Setting JPanel colors has no effect in the toolwindow

        this.contentFactory = ContentFactory.getInstance();
        this.contentManager = toolWindow.getContentManager();

        JPanel jPanel = new JPanel(new BorderLayout());
        JLabel jLabel = new JLabel("hi, is my chat");
        jLabel.setOpaque(true);
        jLabel.setBackground(Color.RED);
        jPanel.setBackground(Color.RED);
        jPanel.add(jLabel, BorderLayout.CENTER);

        Content content = contentFactory.createContent(jPanel, "", false);
        contentManager.addContent(content);

How to solve the problem of color in the desired effect? Thank you