Manual:Coding conventions/LESS

To be moved to Manual:Coding_conventions/LESS if Requests for comment/LESS is approved:

This is based on Manual:Coding_conventions/CSS.

Whitespace

 * One selector per line
 * Opening braces for the LESS rule or subrule on the same line as the (last) selector
 * Indent each declaration with a tab, with additional indents for subrules (e.g. descendants).
 * No space before the colon
 * 1 space between the colon and the value
 * a semi-colon after each declaration (including the last one)
 * Closing braces unindented back to the left
 * noflip annotation for CSSJanus and CSSMin should be on their own line, above the LESS rule they're for. Embed should call embed mixin.
 * An empty line between one LESS rule and the next.

Imports
TBD