Formula for changing colour of row based on drop down menu

Hi everyone 

I have managed to make a drop down list but I am struggling to find the formula to change the row of the table to a different colour based on the drop down menu.

For reference I have Complete, In Progress, and Not started in my drop down menu and want to be able to change the whole row to green for complete, yellow for in progress and red for not started. I have managed to change the colour but only for the drop down menu, not for the whole row.

Thanks in advance.