anchor.diff:        },
         {
           extend: 'pdf',
  -        className: 'btn-sm btn-outline-secondary',
           orientation: 'landscape',
           pageSize: 'A4',
           exportOptions: {
  
positive.code:     buttons: [
        {
          extend: 'copy',
          className: 'btn-sm btn-outline-secondary',
          exportOptions: {
            columns: ':visible',
            search: ':applied'
  
negative.code:       },
        {
          extend: 'excel',
          exportOptions: {
            columns: ':visible',
            search: ':applied'
  