I think you are looking to separate design from your code,
HTML::Template is one popular way to do this. Basically the goal is to have the look and feel of the web pages be left up to the designers (skins), and your code supply the dynamic data. A link that may give you some insight to the thinking behind this next logical step in design is
here (offsite google cache), the article shows a design/code combined project that migrates to a split entity using a template system.