I want to add some extra HTML to the control panel for all users to navigate back to the main site, but when I added the code I needed in admin-header.php it broke the the CSS file and my control panel was naked. But the code was there fine. Just looked crazy.
Can this even be done and why would the CSS file break? And all of the CSS files were linked properly.
Also note, I also added a few styles to wp-admin.css