Make categories bolder in category listing

-- url of the page with the problem -- : fireworksland.com/index.php
-- HikaShop version -- : 4.1.0
-- Joomla version -- : 3.9.8
-- PHP version -- : 5.6.30
-- Browser(s) name and version -- : Safari 11.1.2

Attached is a screen shot of my site's home page. The home page is a category listing. I only have 3 categories. (The 3 sections below the categories are from a custom module.)

I would like the category names to be bolder. I.e., Fireworks Shirts, Fireworks Videos and Fireworks Catalogs to be bolder.
How would I do this? Through CSS? I could not find any settings in the configuration or menu options.

Thank you for your help.

Thank you!