[Plugin: AddToAny: Subscribe Button] Where does CSS Code get Added?

This may sound dumb – but where does the add to any css custom code get added, like this to remove their “Make Money” tab in the pop up?

<style type=”text/css”>
#a2apage_PTZ { display:none !important; }
</style>

Thanks!

https://www.ads-software.com/extend/plugins/add-to-any-subscribe/