Thread:Project:Support desk/CSS is not loading properly/reply (17)

If your variables.less is missing some variables, the less compiler will not compile the CSS output properly, and you'll get an error like this:

/* exception 'Exception' with message 'variable @collapsible-nav-heading-color is undefined: failed at `ight.woff") format("woff"),` /var/lib/mediawiki/skins/vectorcatalyst/catalyst.less on line 17' in /var/lib/mediawik/includes /libs/lessc.inc.php:3581 Stack trace: */
 * 1) 0 /var/lib/mediawiki/includes/libs/lessc.inc.php(2125): lessc_parser->throwError('variable @colla...', 351)
 * 2) 1 /var/lib/mediawiki/includes/libs/lessc.inc.php(1880): lessc->throwError('variable @colla...')
 * 3) 2 /var/lib/mediawiki/includes/libs/lessc.inc.php(1503): lessc->get('@collapsible-na...')
 * 4) 3 /var/lib/mediawiki/includes/libs/lessc.inc.php(714): lessc->reduce(Array)
 * 5) 4 /var/lib/mediawiki/includes/libs/lessc.inc.php(311): lessc->compileProp(Array, Object(stdClass), Object(stdClass))
 * 6) 5 /var/lib/mediawiki/includes/libs/lessc.inc.php(249): lessc->compileProps(Object(stdClass), Object(stdClass))
 * 7) 6 /var/lib/mediawiki/includes/libs/lessc.inc.php(223): lessc->compileCSSBlock(Object(stdClass))
 * 8) 7 /var/lib/mediawiki/includes/libs/lessc.inc.php(719): lessc->compileBlock(Object(stdClass))
 * 9) 8 /var/lib/mediawiki/includes/libs/lessc.inc.php(311): lessc->compileProp(Array, Object(stdClass), Object(stdClass))
 * 10) 9 /var/lib/mediawiki/includes/libs/lessc.inc.php(249): lessc->compileProps(Object(stdClass), Object(stdClass))
 * 11) 10 /var/lib/mediawiki/includes/libs/lessc.inc.php(223): lessc->compileCSSBlock(Object(stdClass))
 * 12) 11 /var/lib/mediawiki/includes/libs/lessc.inc.php(719): lessc->compileBlock(Object(stdClass))
 * 13) 12 /var/lib/mediawiki/includes/libs/lessc.inc.php(311): lessc->compileProp(Array, Object(stdClass), Object(stdClass))
 * 14) 13 /var/lib/mediawiki/includes/libs/lessc.inc.php(249): lessc->compileProps(Object(stdClass), Object(stdClass))
 * 15) 14 /var/lib/mediawiki/includes/libs/lessc.inc.php(223): lessc->compileCSSBlock(Object(stdClass))
 * 16) 15 /var/lib/mediawiki/includes/libs/lessc.inc.php(719): lessc->compileBlock(Object(stdClass))
 * 17) 16 /var/lib/mediawiki/includes/libs/lessc.inc.php(189): lessc->compileProp(Array, Object(stdClass), Object(stdClass))
 * 18) 17 /var/lib/mediawiki/includes/libs/lessc.inc.php(829): lessc->compileImportedProps(Array, Object(stdClass), Object(stdClass), Object(lessc_parser), '/var/lib/mediaw...')
 * 19) 18 /var/lib/mediawiki/includes/libs/lessc.inc.php(189): lessc->compileProp(Array, Object(stdClass), Object(stdClass))
 * 20) 19 /var/lib/mediawiki/includes/libs/lessc.inc.php(829): lessc->compileImportedProps(Array, Object(stdClass), Object(stdClass), Object(lessc_parser), '/var/lib/mediaw...')
 * 21) 20 /var/lib/mediawiki/includes/libs/lessc.inc.php(311): lessc->compileProp(Array, Object(stdClass), Object(stdClass))
 * 22) 21 /var/lib/mediawiki/includes/libs/lessc.inc.php(305): lessc->compileProps(Object(stdClass), Object(stdClass))
 * 23) 22 /var/lib/mediawiki/includes/libs/lessc.inc.php(220): lessc->compileRoot(Object(stdClass))
 * 24) 23 /var/lib/mediawiki/includes/libs/lessc.inc.php(1927): lessc->compileBlock(Object(stdClass))
 * 25) 24 /var/lib/mediawiki/includes/libs/lessc.inc.php(1950): lessc->compile('/*?** Catalyst ...', '/var/lib/mediaw...')
 * 26) 25 /var/lib/mediawiki/includes/libs/lessc.inc.php(2022): lessc->compileFile('/var/lib/mediaw...')
 * 27) 26 /var/lib/mediawiki/includes/resourceloader/ResourceLoaderFileModule.php(809): lessc->cachedCompile(Array)
 * 28) 27 /var/lib/mediawiki/includes/resourceloader/ResourceLoaderFileModule.php(719): ResourceLoaderFileModule->compileLESSFile('/var/lib/mediaw...')
 * 29) 28 /var/lib/mediawiki/includes/resourceloader/ResourceLoaderFileModule.php(692): ResourceLoaderFileModule->readStyleFile('vectorcatalyst/...', false)
 * 30) 29 /var/lib/mediawiki/includes/resourceloader/ResourceLoaderFileModule.php(321): ResourceLoaderFileModule->readStyleFiles(Array, false)
 * 31) 30 /var/lib/mediawiki/includes/resourceloader/ResourceLoader.php(812): ResourceLoaderFileModule->getStyles(Object(ResourceLoaderContext))
 * 32) 31 /var/lib/mediawiki/includes/resourceloader/ResourceLoader.php(546): ResourceLoader->makeModuleResponse(Object(ResourceLoaderContext), Array, Array)
 * 33) 32 /var/lib/mediawiki/load.php(43): ResourceLoader->respond(Object(ResourceLoaderContext))
 * 34) 33 {main}

To fix this, make sure you have these defined in your skin's less variables file (usually variables.less) e.g.

@collapsible-nav-heading-color: #4d4d4d;