Hi there,
most pages have an main id like "osbcontainer" or "servicesListing" which is quite nice to style the site.
The checkout page however just comes with the class "row-fluid" which is used all over the page....
So a special id at that point as well would be nice.
Even better would be a "wrapper"-class like "oss-container" or whatever, which wraps every oss-content the front-end.
Greets,
Thilo