Different styles for some of the cells in Excel

Hello

I´m coding a script for excel spreadsheets and I require different styles for some of the cells.

This is my code:

var LenguaBd=Context.getSelectedLanguage();

var Modelos=ArisData.getSelectedModels();

var modelo= Modelos[0];

var sFileName = "MatrizPuestos.xls";

var sTemplateFileName = "PlantillaMatrizPuestos.xls";

var oXlsWorkbook = Context.createExcelWorkbook(sFileName, Context.getFile(sTemplateFileName, Constants.LOCATION_SCRIPT));

var oXlsSheet = oXlsWorkbook.getSheetAt(0);

var oXlsFont = oXlsWorkbook.createFont();

var oXlsStyle1=oXlsWorkbook.createCellStyle(oXlsFont, 0, 0, 0, 0, 0, 0, 0, 0, Constants.ALIGN_LEFT, Constants.ALIGN_CENTER, 0, 0, Constants.NO_FILL);

    oXlsStyle1.setFillPattern (Constants.SOLID_FOREGROUND );

    oXlsStyle1.setFillForegroundColor (Constants.C_GREY_80_PERCENT);

var oXlsStyle2=oXlsWorkbook.createCellStyle(oXlsFont, 0, 0, 0, 0, 0, 0, 0, 0, Constants.ALIGN_LEFT, Constants.ALIGN_CENTER, 0, 0, Constants.NO_FILL);

    oXlsStyle2.setFillPattern (Constants.SOLID_FOREGROUND);

    oXlsStyle2.setFillForegroundColor(Constants.C_LIGHT_BLUE);

   

    var oRow=oXlsSheet.createRow(0);

        var oCell = oRow.createCell(0);

        oCell.setCellValue("Niveles");

        oCell.setCellStyle(oXlsStyle1);

      

        oCell = oRow.createCell(1);

        oCell.setCellValue("Nombre Proceso");

        oCell.setCellStyle(oXlsStyle2);

   

   

    Context.setSelectedFile(sFileName);

    oXlsWorkbook.write();

why did the first style not used? I need a header, but the cells have no different background.

Any help would be appreciated.