yo fam! on your zencart admin pages
go to Tools -define pages editor - and at the top your screen there is a "plain text/html area" dropdown box. keep it as plain text and add what you like, or if you flick to the html area you can see it as it would appear to a customer.

or on css. find the define_main_page.php but i hate touching it.
peace!

p.s. help me as well bro.
i got attributes grid add on. i want it to display vertically, but when i follow instructions i get an annoying radio box "quantity [.]" on the screen, how do i get rid of it