Well I did manage to get Opera7 to use the full percentage of the width of the column, but it caused me to add more code to hide it from IE6. I added a padding-left of 125% to the legend, and positioned the h3 inside the legend tag at -125%.
A couple problems with this though:
- breaks IE6, need workaround code
- breaks Op6, looks horrible
- uses magic numbers (125%) that just work, and have no relation to the rest of the site.
As such I'm going to ignore this slight display problem, and as it works for more browsers correctly than works for Opera 7 and annoys other browsers.
I am considering not even using the fieldset for this, but I think it's suited for it if I can just find a satisfying solution for most browsers that degrades well in the rest.
Now my experiment comes to an end. It was becoming too much trouble to try and stylize fieldset in such a manner, especially when I found out that legend tags cannot contain <h3> tags and vice versa. Oh well, it was fun, and worth a shot. It's too bad though, because that would've been more semantically correct.
The above link will no longer serve as an example I'm afraid, as I'll be modifying it.