Horizontal scrolling with flexible number of items/width

I followed this tutorial: Horizontal scrolling | Webflow University

And it works great (Nav Bar Show/Hide)

However, if I have to hand the site down to someone less technical and who does not need an extra layer of instructions, it IS HARD to have to add an extra ITEM to the scrolling frame list.
Adding an item, will require updating the height of the scrolling track and the animation X-value to -100 * N vw, where N is the number of items.

Is there a more elegant solution? Wouldn’t there be a way to use the CMS items and never have to update the style/animation X value?

Here is my public share link: LINK
(how to access public share link)