Sub-Subcategories?

Hi all, I have just installed Discourse for the first time and I must first of all say it is extremely nice and overwhelming at the same time, I have struggled in finding out how to make a Sub-Subcategory or something of it’s nature, I have seen another website which uses Discourse to set their forums up how I am trying but I cannot seem to find out how they have used this feature, any help will be greatly appreciated.

Below is an image of their forums.

You should probably use tags more so than creating separate sub-sub-[…] categories, as you can only create categories and sub-categories.

I think I explained my issue incorrectly, I am wondering how I add the headers like “Cfx.re” and “FiveM” so I am able to separate my categories to the relevant area as currently everything is placed under one section whereas on the Forums you moderate its under relevant areas.

Below is a picture of my Categories page on my forums so you can compare what I mean:

Oh, that is obtained through custom CSS. It hasn’t been publicly posted, but you could perhaps try contacting them to see if they’d be willing to post it. Otherwise, I guess the logic would go as far as setting an image based on whichever class is being used for the category div of the category you wish to put a header above, also adding some padding to the bottom of (in this case, ‘Cookbook’).