code: @Override
      void appendTo( StringBuilder target, LessExtendMap lessExtends, CssFormatter formatter ) {
          if( hasContent( lessExtends ) ) {
              formatter.startBlockImpl( selectors );
              for( CssOutput cssOutput : results ) {
                  cssOutput.appendTo( target, this.lessExtends, formatter );
              }
              formatter.endBlockImpl();
          }
      }
docs: {@inheritDoc}