At the beginning of this chapter, we took a brief look at the file structure of the Bootstrap library download; now is a perfect opportunity to revisit this in more detail.
If we open a copy of the downloaded archive and navigate to the root level of the less subfolder, we can see these mixins are spread over 29 mixin files, which can be split into these categories: Utilities, Components, Skins, and Layout.
Most of these mixins are concerned with providing Bootstrap its core styles—the ones that are of particular interest are:
bootstrap.less: This is the master Less file that, when compiled and minified, will formbootstrap.min.csstheme.less: This contains some core theme styles
Note that if you download the version of Bootstrap directly from GitHub, then you will notice this additional folder:
This folder contains the mixins required to control the styling for the theme; if we peek inside the folder, we will see the additional mixins that are used to create what...