Ability to bulk edit design of Ideas Portals

We currently have 30+ ideas portals which all have the same config design, but different URLs for different products. When we need to make a change to an email template, or the HTML, or terminology - we need to manually update EACH portal which takes a lot of time and is tedious. Would be much more effective to have a master "style" which can be applied to ideas portal(s) so we can make a change in the master, and for this to apply to each ideas portal