Styling a Page containing a sections list

I have a page with multiple sections. Each section is composed of 2 columns. In the left column there is a Person element. In the right column there is a 3 tabs element. I need to repeat the section for every person composing the research group.
So, I duplicated the section and changed parameters (name, picture, text, etc.)
I would like to customize the obtained sections list, using the file custom.css. How can I give a generic name to the <div> so that I can apply some properties to all sections, also on different pages with the same structure?
If I can’t do it this way, could you please suggest an alternative?
I’m using the HelixUltimate template on Joomla 5.
Thank you
Carmen