What are SASS functions and how do you define one?
Description : Defining and using functions in SASS.
Answer :
SASS functions are used to perform calculations and return values for use in your stylesheets. You define a function using `@function`, and it must return a value with`@return`. For example,`@function calculate-rem($px) { @return $px / 16px + rem; }` defines a function that converts pixel values to rem units, which can be used throughout your stylesheet.