Taking an Element out of an HTML Page

Taking an Element out of an HTML Page

I am testing out with a different way of menus. My code is here. The code
is to make sure that when the id "hub" is clicked, "test" appears. When
hub is clicked again, "test" disappears. The code, when run, opens test,
doesn't let you click it again, but it doesn't delete "test" (as there is
no code for it).
My question: How would I delete the variable "test" from the document but
not to delete the variable forever, as I would need to use it later? Would
.replace();
work?
Thanks in advance!