How to conditionally format background colour based on a date column

Hello People,

please i need help to conditionally format background colour on a table on my dashboard. 

I want a situation where "Expired" changes to a red background, and "Valid' changes to Yellow background when it is remaining 1 month to certificate expiration, else Valid should be green. Using the example below can someone please help me with the solution to this? 

Note: the "expired" and "valid" on my table are calculated columns based on date columns for both certificate 1 and 2 in my query editor.

please this is very urgent. i would really appreciate all the help i can get