In this chapter, you will learn the following topics:
Using nested selectors
Creating more intuitive code and making inheritance clear
Referencing parent selectors with the & sign
Using multiple & signs to refer to the parent selector more than once
Using the & operator to change the selector order
Utilizing the @extend directive
Using placeholder selectors with the @extend directive
Using the @extend directive together with the @media at-rule
Using the @extend directive with care
Emitting rules at the root of the document
Avoiding nested selectors too deeply for more modular CSS
Applying the OOCSS, SMACSS, and BEM methodologies