Any pre-process stylesheets will go in this directory. For Bootstrap-based projects, this means the Boostrap LESS distribution; for most other projects, it will be Sass files.
Typically, the base directory structure will include:
+- /Base
+- /Components
+- /Helpers
+- /Layout
+- /Overrides
+- /Vendor
+- /Views
+- _variables.scss
+- Style.scss
Note: For more information, see Ignia's Sass structure.