how to make columns name of cross-tab grey color

Hello expert,

when I am creating a cross-tab, I want to make columns name of cross-tab grey color. please tell me how to get it. currently I work around to insert a text and make it grey color, and cover and align with back column names. but it is hard to make them align perfectly, I tried adjust sized , but still can`t make them match, please help me to resolve it. appreciate very much.