LESS for WP

header.php

<?php
require 'modules/lessphp/lessc.inc.php';
try {
    lessc::ccompile(get_stylesheet_directory() . '/style.less', get_stylesheet_directory() . '/style.css');
} catch (exception $ex) {
    exit('lessc fatal error:<br />'.$ex->getMessage());
}

?>

<link rel="stylesheet" type="text/css" href="<?php bloginfo( 'stylesheet_url' ); ?>" media="screen" />

style.less

/*
Theme Name: Template Name
Version: 1.0
Description: Description
Author: Tangram
Author URI: http://www.wearetangram.com
Template: child-theme-of
*/

@import url("../theme/style.css");

@white: #fff;
@border-dark: #575656;
@tangram-red: #e30613;
@tangram-green: #2fac66;
@tangram-blue: #2daae1;

...