Re: width of content+padding versus border+margin

> > I'm trying to create H2 output such that the content appears with a
> > background colour that occupies an area only moderately larger than the
> > content itself. 
[...]
> <style>
>   span {
>     display:inline;
>      background: #066; padding: 3pt;
>   }
> </style>
> 
> <H2><span>content</span><H2>

That works, but any approach that would require modifying all the source
documents is not an option.

From section 10.3.3, it looked like it should do what I want if I were to
specify border, padding, margin-left, and set margin-right to "auto". Am I
not reading that correctly?