Putting Categories into Rows

Please see https://ratraceremedies.com/articles for reference. The home page is being used to as a category index instead of for listing posts.

I’d like to separate that one long list into multiple columns (perhaps 3) of categories. It has to be dynamic, so as I add categories, the columns lengthen evenly.

For example:

8 categories
1 4 7
2 5 8
3 6

10 categories
1 5 9
2 6 10
3 7
4 8