Excel Cell Color

How do I change the color of the text in a cell in Excel. I am using the following code.

Code:

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Excel.Application excelApp = new Excel.ApplicationClass();
Excel.Workbook excelWb = excelApp.Workbooks.Add(Type.Missing);

Excel.Worksheet excelWs = (Excel.Worksheet) excelWb.ActiveSheet;

excelApp.Visible = false;
excelWs = (Excel.Worksheet)excelWb.Worksheets[1];

((Excel.Range)excelWs.Cells[1, 1]).Value2 = "Test";

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