Overview

Metronic uses SASS , the most powerful CSS preprocessor for handling the theme css efficiently. Sass is the most mature, stable, and powerful professional grade CSS extension language in the world.

Components

Components folder in /src/sass/components/contains SASS code that customizes the core Bootstrap components to match the Metronic's own design system and custom components. Both Metronic and Bootstrap components are customized in /src/sass/_variables.scss.

Bootstrap Variables

In /src/sass/_variables.scssfile, Metronic deeply customizes the standard Bootstrap components by following the best practices explained in the official documentation.

Custom variables that used to customize Bootstrap components are marked with Custom variablecomment in _variables.scssfile.

Override Variables

If you like to change the Bootstrap theme colors, border radiuses, font family and other variables, we suggest using _variables.custom.scssfile so you keep your own changes separated from future updates to avoid conflicts. All variables to override in this file should be set without the !defaultattribute to prioritize your code change.

Layout

Layout related SASS code is located in /src/sass/layout/folder. This folder contains the layout's markup and SASS variables files as explained in the below table:

File	Description
`_variables.scss`	Variables used by Layout Partials. You can easily change Aside width, header height and other common properties.
`_layout.scss`	Defines main layout and its dependencies.
`_main.scss`	Defines base markup and styles.
`_header.scss`	Defines base layout markup and styles.
`_footer.scss`	Defines footer markup and styles.

Compilation

Metronic compiles layout, components(including the Bootstrap & custom components) into the main bundle: dist/assets/css/style.bundle.css.
The custom SASS files are compiled separately into CSS folder: dist/assets/css/custom
All 3rd-party plugins css files are bundled into the plugins bundle CSS file and globally included in all pages. dist/assets/plugins/global/plugins.bundle.css.