Change amount of Isotope elements in one row?

Good Day!

I already had a look at a the documentation of Isotope but I couldn’t get the amount of elements in each row to change (preferably 5 or 6) https://isotope.metafizzy.co/options.html#element-sizing :unamused:

https://www.forcewerk.com/2018/wordpress/

Could anyone please point out what the best approach would be? I’m using a WordPress template and even when I change it in the settings of the template I can’t see any effect. So I’d like to hard-code the JavaScript directly into the header if necessary. The author/support of the theme didn’t get back to me so far…

Thanks so much!
Kind regards