code: @Override
      protected void configureCssClassesByLevel(CssClassesByLevel cssClassesByLevel) {
          super.configureCssClassesByLevel(cssClassesByLevel);
  
          if (this.configurer != null) {
              this.configurer.configureCssClassesByLevel(cssClassesByLevel);
          }
      }
docs: /*
  (non-Javadoc)
  @see
  es.sandbox.ui.messages.spring.MessagesConfigurationSupport#configureCssClassesByLevel(es.sandbox.ui.messages.
  context.CssClassesByLevel)