Can I use conditional formatting to change the color of a cell based on other cells being blank?


I have a smartsheet where I have data being added from multiple cells in different categories. At the bottom of this sheet I have the data grouped into 7 categories that pull from individual cells above and add them together based on one specific category. What I would like is that grouped data to turn green if all the cells it is adding together are filled in and red if there are any cells that are empty. Is there a way to do this?