Widget _buildPadding(BuildContext context) {
  var style = TDCellStyle.cellStyle(context);
  style.padding = const EdgeInsets.all(30);
  return TDCellGroup(
    theme: TDCellGroupTheme.cardTheme,
    cells: [
      TDCell(arrow: true, title: 'padding-all-30', style: style,),
    ],
  );
}