Resources https://www.codecademy.com/courses/learn-css-variables-and-functions/lessons/learn-css-variables https://www.codecademy.com/courses/learn-css-variables-and-functions/lessons/learn-css-functions https://www.youtube.com/watch?v=PHO6TBq_auI&list=PL4-IK0AVhVjOT2KBB5TSbD77OmfHvtqUi (Kevin Powell)