Welcome to the Q&A Forum

I would not recommend creating multiple pages for each, that would cause duplicate content issues.  I would try to use all three interchangeably on one landing page so the one page ranks for all three.

You only want separate pages if the keywords are different enough to warrant new and different content.  These are too similar for this and would cause a usability issue if you wrote unique content for each one.

After an hour or so of messing around with it, I found a Solution!

So you have to have two rules.

First one is Cell is Empty, set the background color to white (not sure why this is needed, but it is crucial for it to work)

Second rule is Custom Formula is =len(B2)>150, set background color to red (this will set it to red if the their is over 150 characters.

This test spreadsheet really helped me out. (gotta make a copy to mess with it)
https://docs.google.com/spreadsheets/d/1ScDqtZvhsmf2iByAuxHBu0-ESpX_TE5pdtBvAxOJ99E/edit#gid=1620525099

Your welcome,
Chris

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