While we're on the subject of tags & CSS, the [cmd] tag doesn't work correctly either, it enters a new line where it shoudn't.
# ls (This is all a single line, press quote to see).
This makes no sense, how is this different from [code]? The idea behind [cmd] was that you could easily highlight shell commands inline.
Change the display: inline-block; to display: inline; and it should be fine.
UNIX was not designed to stop you from doing stupid things, because that would also stop you from doing clever things.