The theme editor is designed to make it easy select a theme and quickly adjust the colours.

• Each new site has a preselected theme.
• Each theme has a default colour scheme.

A theme is defined by a single .less variables file. It includes custom settings for everything from colour and typography, to design elements such as border and panel spacing.

• When changes are saved using the theme editor, a custom minified CSS file is generated along with a .less file containing the values changed in the editor.
• When the live website is rendered, the compiled minified CSS file is used.
• When the stage is edited once again, the original .less theme variables file is loaded along with the custom .less variables file.

This makes it possible for the original theme to be extended. The user only needs to Edit and Save to regenerate the custom CSS.

At edit time, the less files are compiled and a preview rendered using the Live Less Theme Customizer.

http://demo.virtuosoft.eu/live-less-theme-customizer/examples/bootstrap/customizer.html

A new theme could be created using the Advanced Editor.