Applying fixed page width?

Hey all,

A question about page width in the Pinboard theme.

All my pages in the navigation menu are all the same width (ie. http://the-wolf-and-i.com/contact/), but when I create sub-pages they seem like they have been stretched so that everything is slightly larger (ie. http://www.the-wolf-and-i.com/contact/contact-form/).

Is there a way to have a fixed – width for all the pages (preferably to the larger of the two). And does that also mean that I need to then re-edit all the typography elements to have them match up?

Cheers, Mike