how to change label color

Hi, I want to change the label color when i click on a button, how can I do this?

A simple snippet to use as example:

https://snippet.webix.com/46gxoh86

Hello @AndreaC,
You can use webix.html.addCss and webix.html.removeCss:
https://snippet.webix.com/29j54e99

Thank you!