Sass is the most mature, stable, and powerful professional grade CSS extension language in the world.
Learn more about SASS on their official page: http://sass-lang.com/

In order to enable SASS the following setup should be done:

• Open Terminal App on your Mac or Windows Command Line (CMD) on you windows machine
• Browse to the project folder:
  $ cd myApp
• Run the following command to setup SASS:
  $ ionic setup sass
• Run the following command to view the theme:
  $ ionic serve

FILES STRUCTURE

• scss – is where your SASS file are stored.
  • ionic.app.scss – all imports of needed files for the project
  • layout – the app styling is done in this folder
    • _styles.scss – in this file we have overwritten some default styles of Ionic Framework and we have imported the SCSS files for different pages at the bottom
    • _side-menu.scss – in this file we have written the CSS for the side menu
      • pages – this is where the CSS for every single page type is written
  • modules – styling of additional modules, added to the theme, like our Social Sharing Module
  • utilities – SASS Mixins and Variables