Possible to put some kind of if then test in screenrc?

[David Woodfall]

I have a hardstatus backtick command that prints CPU %. I would like
to change the hardtstatus text colour to bright red if it goes over
90%.

Is this possible?

I tried first using bash colour escape codes, and then normal screen
colour codes like %{b .r.}, but it prints the codes verbatim rather than
as colour codes.