Go through these steps hope it help you -
Microsoft Office Excel 2007 and 2010
Start Excel, and then open the workbook. Click the Microsoft Office Button, and then click Excel Options. Click Save. Next to Choose what colors will be seen in previous versions of Excel, click Colors. Click the color that you want to change, and then click Modify. Use one or more of the following procedures: To replace the selected color on the palette with a different standard color, click the Standard tab, and then click the color that you want. To change the hue or another aspect of the selected color, click the Custom tab, and then change the options. Click OK. Repeat steps 5 through 7 as needed, and then click OK. Click OK to close the Color dialog box. Click OK to close the Excel Options dialog box.