code: private void updateStyle(JPanel c) {
          SeaGlassContext context = getContext(c, ENABLED);
  
          style = SeaGlassLookAndFeel.updateStyle(context, this);
          context.dispose();
  
          // Set the opacity according to whether the background has been set.
          // Don't set it if the user has already set it.
          LookAndFeel.installProperty(c, "opaque", !(c.getBackground() instanceof UIResource));
      }
docs: Update the Synth style if a property changes.
  
  @param c the panel.