Can I change the Design (Background Color/Font Color) of a section of my Flatiron site without changing the entire site's Design?

Hi everyone, 

I am trying to find out if it's possible to change the Design of a page/section of my client's website (built on Flatiron template) without changing the Design of the entire site. The site is currently white with dark grey text. I am building a new page/section for Filmwork, and my client wants a black background with white text for this section for a more cinematographic effect. I can see how to change the entire site's design but not a single section. Is this possible and if so, how do I accomplish this? I am not versed in CSS nor am I an engineer. Any help would be greatly appreciated.

You can share link to page where you have problem, we can give CSS to solve these