Hi,
You can use custom CSS for this.
Would you please share which template you are using? If it's simply the helix-ultimate then please make sure you've enabled this
http://prntscr.com/nur7d6
Also, make sure you've cleared all caches from Joomla and browsers and finally make sure you did not use any inline CSS in layout builders
http://prntscr.com/nuspvw
And if you are using any of our one-click installer templates then you need to know that one-click installer template doesn't include any preset. Since all the pages are created with a page builder that's why you can change that css only using the page builder.
Thanks
