What is a CSS preprocessor and why would you use one?

@dedrick 

A CSS preprocessor is a tool that extends the functionality of standard CSS by introducing features such as variables, functions, and mixins. It essentially allows developers to write more efficient and modular CSS code.

Using a CSS preprocessor can make your stylesheets easier to manage and maintain, as well as improve the overall development process. Here are a few reasons why you might want to use one:

1. Reusability: CSS preprocessors allow you to define reusable code snippets called mixins. This means that you can define a set of styles once and use them throughout your stylesheet or across multiple stylesheets.
2. Variables: With a preprocessor, you can define variables to store commonly used values such as colors, font sizes, or padding values. This makes it easier to update these values throughout your stylesheet by simply changing the value of the variable.
3. Nesting: Preprocessors allow you to nest your styles in a way that reflects the structure of your HTML markup. This can make your code more readable and easier to understand.
4. Functions: CSS preprocessors provide functions that can help simplify complex calculations. For example, you can use a function to automatically calculate the size of an element based on its parent container.

Overall, using a CSS preprocessor can help you write more efficient and maintainable code, and can save you time in the long run.