backgroundcolor of popup-window

Hello,
I want to change the color of the popup-window, that opens when I click on an marking-point.
The inspector tells me, that it is a inline-css, but I cant find the origin where it is defined.
The website is: www.bio-oikos.de/index.php/unsere-liefer...htskarte-lieferanten
Thank you for help.
With regards Frank

Hi Frank.
It caused by your CSS in template.
For example, if you have knowledge how to get information, you can see override.

You can have 2 ways
1 - direct edit template CSS file, add into the end of this file your styles, for example, overrides for google's classes, or for my classes.
In common way I added styles everywhere you can alter it.
2 - you can add new CSS file into server, and add it's loading in map option in "Advances options" in field "Additional CSS style files for loading".

Moreover, you can use CSS Class on this tab to add map div class, and you can more flexible alter your styles (as you can know, you can access to div by class name, and to div content by using top div class name or ID)

Add with !important to override