Css question (theme quark)

Hello,
I'm making a grav-site with the quark theme.
I would like to know how I can custom background color in the menus that fold/unfold in the navbar ?

@pzul, It depends on how fluent you are with scss...

Plain css:

• Create an inherited theme.
  If you don't all changes will be lost when Quark gets upgraded.
• Create file '/user/themes/mytheme/css/custom.css' and add you css to the file.
  This file overrides the same file provided by theme Quark.

Using scss:

• Create an inherited theme
  If you don't all changes will be lost when Quark gets upgraded.
• See the documentation on using scss.

I don't know scss.
The custom.css file is created, but impossible to find what kind of class or id to use in order to refer to these unfold part of the navbar...
I only succeeded to change the entire navbar background color...

@pzul, Have you been able to make some progress?

No progress... I'll try after installing an IDE... It's not a prioriy for me but if a little frustrating ;-)