Getting rid of the BP admin bar on certain blogs

Hi: We're running a multisite setup off of WP 3.2.1 and BP 1.2.10. We're also using Pro Sites to let bloggers upgrade. One of those upgrades is Premium Themes - which differ from our regular themes (the fabulous Farm Pack, thank you so much, incsub :slight_smile: in that all our Premium Themes are responsive, so they'll reformat real nice for mobile.

We're running our setup so that the BP admin bar is shown for all visitors, both logged-in and not; and so it shows on all our members' blogs as well. However, I'd like the admin bar to *not* appear on the Premium responsive themes for anyone, logged-in or not.

It seems the easiest way to do this would be to hide the admin bar via some sort of CSS invisibility attribute that we'd add to all the style sheets of the responsive themes. Problem is, I don't know what the syntax of that CSS code would be. Can anyone here help me out with this? My thanks in advance --