Conditional Formatting - past due dates

I have a formula in B2 to display the date that appears in A2, plus 7 days. I typed "7" into Sheet 2, C2, and refer to that cell in the formula.

Now I would like to highlight B2, if today's date is more than 7 days past the date in A2. In other words,



A2 = 6/1/14
B2 = 6/8/14 with formula: =IF(A2="","",(SUM(A2+Sheet2!$C$2)))
Today's date is 6/27/14, so B2 needs to be highlighted in red.

Is there any way to do that?

Thanks!