New(er) Default.css Cleanup from UX Team

As you might have seen a blog post came out in the summer about the process of cleaning out default.css.

Lance Long, a new UX team volunteer, and I picked up the default.css again and worked on it last week. We removed module specific selectors for ease of management and eliminate unnecessary selectors being loaded on the page when you don't need it along with some CSS shorthands. 

For module specific CSS, we move them to the following files and created a few gemini issues:

• File Manger: DNN-13498  
• Wizard: DNN-13499  
• Event Viewer: DNN-13930