outline .close-nav-toggle

Hi,

I set up a blog with twentytwenty. smaller than 1000px the mobile-menu comes up and when i click on the toggle it is shown with an outline or border around .close-nav-toggle – I do not want this.

.close-nav-toggle {outline: 0;} does not work – some variants of it alos not working incl. with !important

In this case i need some help. thanks in advance.