I want to setup a spreadsheet with a list of mandatory courses that should be completed every 1 to 3 years and I would like to setup a traffic light system against each course listed so that:• When the course has been completed the cell for that particular course is 'Green'; • When the course is within one month of its time expiry, the cell turns 'Amber';• When the course has gone over its time expiry, thjen the cell turns 'Red';Is anyone able to provide some guidance on how I can achieve my goal.Many thanks in advance.