Replace Theme's Gallery Behavior with Ghost Default

Hi there, I’ve posted about this before, but still haven’t figured out how to implement it well. I’m using the Nurui theme for my blog, and the way it implements the gallery is a bit different from the Ghost native version.

You can see the current behavior on the Nurui style guide page, here.

Clicking on an image in the gallery pulls it up in a lightbox, but doesn’t give the option to arrow between images, only to click to shrink down again.

I’d like to overwrite this functionality with the gallery implementation first shown off in Ghost 2.0, here, where clicking an image in the gallery brings it up in the lightbox, allows fullscreen viewing, allows arrowing between images, etc.

What would I need to do to accomplish this? If I find the section responsible for gallery styling in my screen.css file, and replace that with the CSS code listed here, and add a gallery.js file (as posted here) to my assets > js folder, should that do it?