Sidemenu background-color in Ionic-v4

Hi all,

i have a Ionic-v4-app with an sidemenu structured like that:


Now i want the have a background for the whole sidemenu (header, list, content, everything).
But it is unnecessary what i try, i don’t get it working.

I tried a background color for ion-menu and transparent background for header and content, but also not working.