How to change the background color of a modal window

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1

Hello,
i am trying to change the background color of a modal window but even if i set it to !important it does not change.

https://snippet.webix.com/yhd7x747

Thank you.

2

try deeper selector. like .mmm .webix_view or .mmm *
https://snippet.webix.com/29knczg4

3

Thank you.