Welcome a new WebStorm 12 EAP build (144.4199)!
As always, you can download it here or, if you have a previous EAP build (144.3891) installed, you should soon get a notification in the IDE about a patch update.
Support for CSS Custom Properties
WebStorm adds support for CSS Custom Properties based on the W3C recommendations.
You can get code completion for variable names:
From a variable you can jump to its definition with the Cmd-Click (Ctrl-Click), see its quick definition or find its usages.
WebStorm would also validate the default value and parameter info.
Coding ass