Less (sometimes stylized as LESS) is a dynamic stylesheet language that can be compiled into Cascading Style Sheets (CSS), or can run on the client-side and server-side. Designed by Alexis Sellier, Less is influenced by Sass and has influenced the newer “SCSS” syntax of Sass, which adapted its CSS-like block formatting syntax. Less is open-source. Its first version was written in Ruby, however in the later versions, use of Ruby has been deprecated and replaced by JavaScript. The indented syntax of Less is a nested metalanguage, as valid CSS is valid Less code with the same semantics. Less provides the following mechanisms: variables, nesting, mixins, operators and functions; the main difference between Less and other CSS precompilers being that Less allows real-time compilation via less.js by the browser.