Change Cell Color Based on the Last Value in a Column

Hi - am trying to figure out a way to change the color of one cell based on a column of data. Specifically, the last value in that column. This is a spreadsheet to track a project, so you enter the Date Completed (Column G) as you go, which then populates the Variance in Column H. As I enter the completed date, I would like the box over on the right to change color (red, yellow, green) based on the variance, however, I cannot specify one cell and would like to know if there's a way to change the color based on the last value in column H. Does that make sense? So if the last date entered in Column G was on row 34, I would like the color to be based on the value in cell H34. Thank you! excel.png

How would I plug that in to highlight red if the number in column H is >7, yellow if it is >=0 and <7, and green if it is =<0? Would I need 3 separate rules in the conditional formatting?
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