Are you asking for the selector for the profile card? It's #profile_card. (There's also a .profile_container which contains it.)

You can find all this by just right-clicking on it and clicking "Inspect", by the way. That'll show you the HTML for the profile box, and you can refer to each HTML tag by its name (e.g. div), one of its classes preceded by a period (e.g. .profile_container), or its id preceded by a pound sign e.g. (#profile_card).