How do I change color on Menu Bar for PY Environment

This question applies to both Citrix and Fat Client.  I am on EnterpriseOne 9.0 with tools release 9.1.3.4.

I would like to understand how to make the Menu banner across the top of the page a different color for the PY environment.  It helps to identify at a glance which environment I am in during times when I have both environments open.  We had a consultant make this change for us at one point, but somehow it reverted back to the same color as production (blue).  I'd like to understand where this change is made and how to prevent it from changing back.  I think it changed after a package deployment.