Hi,
I am trying to modify the sub-menu in CSS, rounding up the edges. Found an entry on another page that uses Advocat ("border-radius") but can't find the corresponding entry on my end. I use Joomla 3.916, JP-Advocat 1.0.001 and Warp 7.3.36.
Thank you for any help.

Live Url please.
And which submenu? From the main menu or from the menu on the right side?

Usually you can add a radius with this css code.
Add this code to our css/custom.css

.uk-dropdown-navbar {border-radius: 25px;}

www.w3schools.com/cssref/css3_pr_border-radius.asp

That did it. Thanks a lot!

Problem solved.