It seems that fieldset defaults to 100% width of its container. Is there any way that you can have the field set just be as big as the widest control inside the fieldset?
Use display: inline-block
, though you need to wrap it inside a DIV to keep it from actually displaying inline. Tested in Safari.
<style type="text/css">
.fieldset-auto-width {
display: inline-block;
}
</style>
<div>
<fieldset class="fieldset-auto-width">
<legend>Blah</legend>
...
</fieldset>
</div>