LESS is a language that extends CSS by adding new features such as variables, mix-ins (kind of functions), etc... It makes CSS development more efficient and maintainable and is used by one of the major CSS frameworks available: Bootstrap.

Last year, we have integrated the LESS compiler in XWiki. At first, the purpose was to create a new look & feel based on Bootstrap, compatible with existing color themes. Quickly, we have encountered the need to execute some LESS code on-the-fly, and proposing a LESS compiler in XWiki was the unique solution. ...