Disabling the header, navigation and sidebar stuff in a Custom Post Type

Here is my website: https://www.paleoprovidence.com

What I have is a parametric search on the left that allows users to search for restaurants. A list of restaurants results show up. When the user clicks on the restaurant, they are brought to a lightbox in which they can see more indepth information for that restaurant.

Right now, the in depth information for the restaurant is created through a Custom Post Type called “Restaurants”…so all of the restaurants are under this particular kind of post. It makes it easy for me to just add in information to certain fields and have it all display nicely in a content template.

What I want to have happen is: When the lightbox pops up, only the CONTENT for that restaurant post will show up and NOT the header, sidebar, navigation and the whole shebang as it does now. The lightbox should show the simple content of whatever is in that post, white background, nothing else.

I was wondering if there was some <?php if post type = restaurant post then the header, sidebar would be hidden and only the content shows. I have an extremely limited knowledge of PHP and can basically just do copy/pasting of coding with a little substitution where indicated.

Let me know if this is possible!