* Fix all stylelint errors
For any errors that fixing would require changing the output of the css disable stylelint for that line instead of modifying.
* Update quality.py
Make stylelint quality check pass when there are no errors
* Delete empty selectors
Use larger and lighter title font, decrease padding, and use lighter
solid backgrounds instead of gradients. Also, refactor SASS code to
conform better to our new style, including using more specific class
names.
Originally reviewed in #4072
