Update to 5.1.1 broke all site formatting (and Cornerstone no longer works either)

I just updated from a staging/development site to a live site, and all of my formatting is now broken.

URL: http://optimizeyourself.me (I’m currently in maintenance mode)

My staging site info (when everything worked correctly):

Wordpress: 4.8
Cornerstone builder: 1.3.3
Theme: X Theme 4.6.2

Note: My web developer created a child theme that is connected to X.

My live site info with all the broken formatting:

Wordpress: 4.8
Cornerstone builder: 2.0.6
Theme: X Theme 5.1.1

I have also tried updating the theme to ‘Pro’ but the formatting was still broken.

As an additional note, when I revert to X Theme 4.6.2 my site goes back to normal, but because I can’t downgrade my version of Cornerstone, when I open the builder the formatting is incorrect. So I’m stuck.

Please advise. I’m willing to provide WP Admin login info so you can look under the hood and see what is broken. Thank you for the support.

Hi There,

Please backup your website, upgrade and provide login credentials in a secure note.

Thank you

@cracker I’ve moved your issue to a new thread https://theme.co/apex/forum/t/update-to-5-1-1-issues/4695