Customising 2017 theme according to the blog

I have a question about some code in a wpmu blog post:
https://premium.wpmudev.org/blog/twenty-seventeen-wordpress-theme

There is a section in that post called Extra Credit: Create Dynamic On Page Navigation
It allows you to have links in the menu which go to the sections on the 2017 theme frontpage. It works fine BUT all of the links to the sections display as active in the menu (a different color). It is confusing.

It makes sense that it happens with the code but it is weird for a user. If you see this page it looks like blog must be active as it is the only different colored link. It is not active, Home is.

Ideally the section link would highlight when that one was selected. But it would also be ok if Home stayed active and the section links never changed color. Any quick workaround?

Please check the site to see the issue: https://fincamalinche.com/