Integration of Web Page over Portal which is Created in .net

Hi Experts,

I am having a strange Requirment. We have the below Requirment , please guide me .

We are having external facing portal and we want the look and feel get changed so client proposed to to develop a web page in .net and Integrate that Webpage over Portal......I mean The Total home page of Portal including Masthead,Toplevel Navigation , footer all these will be developed in .net and I need to integrate it over the portal 7.31....

Is this possible, if yes how to proceed.

Thanks,

Krishna