Mobile menu not working

Hi,

first issue was, that the mobile menu was not visible at all. I added a menu image via CSS to show it:

.btn-menu:before {
content: url(https://fahrschule1.com/wp-content/uploads/2021/08/2867922_menu_icon.svg);
}

Now I can see the “menu”, but it is not clickable on a mobile device or when using the developer console of the browser and switching to the mobile layout.

Any idea how to fix that? I already tried a lot of CSS hacks described here in the forum without having success.

Thank you

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