Sass: Add alert styling
Don't prevent word wrapping on <code> elements
Add the line number styling to prettyprint elements only
Change invalid input outline color to red
Move the input-inside-label styling to the label section
Add styling for disabled and readonly inputs
Remove the .list-unstyled class - it's not used
Add alignment helper classes
Add clearfix class
Better screen-reader-text

Taken from _s https://github.com/Automattic/_s
Test page: Add disabled elements and remove removed helper classes