Conditional Formatting Based on Several Cells

I have 6 steps in a process, each step has a status cell.
After each step is completed, the worker puts the completion date in the appropriate cell.

I'd like to know when it been over 14 or 21 days since the latest action.

I'd like to have excel check the 6 steps and if the latest date of the 6 steps is over 14 days old... highlight the cell yellow and if the latest date of the 6 is over 21 day old... highlight the cell red.
An example is attached (done manually).

Thanks in advance for any help.

R,
Dave

That works perfectly! Thanks