I'm currently working on a new user registration page containing two sections - personal details and account details. The account details section must remain hidden until the personal details section is complete. There are various reasons why we can't show the account details section at the same time as the personal details section, but while its hidden, there is a large amount of white space where it should be.
In terms of UX (and development) is it good practice to simply hide the white space? Its been suggested I use the space to display product info, but there are about 3 sections above the registration which do that..