Change Toggle Button Color on Sticky Header

Hi there,
I’m using a transparent header and a sticky header when scrolling.

My problem is that I have changed the background color on the sticky header, and the mobile menu button should have a different color, so it could be visible (it’s white and also the background).

My question is how can I change the mobile menu toggle button color?

Is there any settings where I can change it, or it’s necessary to use custom CSS?

Thanks in advance.

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