With the new system the navigation to the site has changed to make access easier. To use html/css or to find your old code these steps will get you there.
Profile: Click Edit (the left panel)
To the right once you are in the edit area you will see Settings Center below that is MyProfile Designer. Click on that it will take you to the profile designer easy wizard.
Scroll down to the Your design code and click advance css box it will take you to your current code.

Hopefully this will help you in finding the area to design your page.