MINI

C:/xampp/htdocs/plugins/datatables/FixedColumns-3.2.2/css/

files >> C:/xampp/htdocs/plugins/datatables/FixedColumns-3.2.2/css/fixedColumns.jqueryui.css

 div.DTFC_LeftWrapper table.dataTable,
div.DTFC_RightWrapper table.dataTable {
  z-index: 2;
}
div.DTFC_LeftWrapper table.dataTable.no-footer,
div.DTFC_RightWrapper table.dataTable.no-footer {
  border-bottom: none;
}