- Box model http://www.w3schools.com/css/css_boxmodel.asp
- What is a rule or "rule set"? http://css.maxdesign.com.au/selectutorial/rule.htm
- Interview Questions and Exercises About CSS https://css-tricks.com/interview-questions-css/
- Categorizing CSS Rules https://smacss.com/book/categorizing
- H5BP's Front-end Job Interview Questions http://h5bp.github.io/Front-end-Developer-Interview-Questions/
- Rails and QA jobs http://joshuakemp.blogspot.com/
- Cracking the Coding Interview: 150 Programming Questions and Solutions http://www.amazon.com/Cracking-Coding-Interview-Programming-Questions/dp/098478280X