SASS

Sass is a CSS preprocessor—a layer between the stylesheets you author and the .css files you serve to the browser. Sass (short for Syntactically Awesome Stylesheets) plugs the holes in CSS as a language, allowing you to write DRY code that’ll be faster, more efficient, and easier to maintain.

If you want to install in basic way then you can refer the sass original page here.

But now a days the installation too have the easy way, if you using Visual Studio Code then follow below 3 steps to install sass easily.

1. Go to visual studio code Extensions and  install Live Sass Compiler 
2. Install and enable the extension.
3. Go to your sass file and you will get the line Watch Sass under footer of the window.
4. When you click the Live sass compiler will open and it will re-code your sass file into style.css.map and style.css.

Example of Grid

SASS file:

$a: gray;

h1 {
    color: $a;
    text-align: center;
}

css file:

h1 {
  color: gray;
  text-align: center;
}
/*# sourceMappingURL=style.css.map */