Hi Noemi,
Maybe this learning path contains, what you are looking for,
Let me know, if you have any issues,
Hope it helps!
To help you, you first need to tell us what this menu evokes? Is it a page template element, a widget? I don't remember it being built in, but I could be wrong
If it's templete, you have to look on the templete settings. If the widget and does not allow you to configure it, you can check in your browser what style configure this element. Then override this style in custom variables
Hi Noemi,
I successfully resolved a similar problem in the past.
step1 : Run your application and inspect the navigation bar
step2 : Change the background color to look like this.
This one ?