on IE on a mac, the grey vertical subheading bar was expanding to fill the whole screen and clicking onto the lab menu item is causing safari to freeze..
fixed the IE problem – specified 12px widths to the grey box and the dynamically created boxes holding each letter.
looking into the safari problem…. CPU goes to 100% when you try to load anything within “the lab” section.
fixed! thanks to tim at twisty.com – he pinpointed it to a problem with the text-transform:uppercase property used on the heading selectors – safari didn’t seem to like applying it when some of the content inside was wrapped in divs and some not – if you remove the spaces, the problem was solved. I wanted to keep the spaces and so I moved that property to the individual divs surrounding each letter.
the same problem presumably doesn’t happen on the vertical submenu because I had already replaced all the spaces with “ ” because without doing that they weren’t creating any vertical space.