Regretfully, that is not possible with X. You will need to switch to Pro in this case. See https://theme.co/pro/
You can override X using a child theme but please note that it requires WordPress development knowledge. If you're not a developer, you'll need to consult with a third party developer.
If you want to learn how to customize X, we have a guide at https://theme.co/apex/forum/t/customizations-best-practices/205. The file that you'll need to override is _navbar.php and it's located in the theme's framework\legacy\cranium\headers\views\global folder.
Please also note that past customization guides might not be applicable to the latest version anymore due to changes or improvements in the theme. It is not feasible for us to update our answers nor create a new one especially that there's a tool that we've created now to build custom headers and footer. That tool is Pro.
Hope that helps and thank you for understanding.