Code:
<fieldset>
  <legend>blah blah</legend>
   blah and blahblah the blah blah ... blah.
</fieldset>
Code:
fieldset {
  background-color: black;
  color: white;
}
legend {
  padding: 2px;
  border: 1px solid green;
}
The Problem: the background-color set for fieldset colours in more than just what's inside the boundaries of the fieldset, i.e. its borders. What happens is it colours in from the top of the legend to the bottom of the fieldset.

What can I do to make it only colour what's inside the boundaries (borders) of the fieldset? I tried putting a <span> inside the fieldset, setting it as block and giving it a background colour, but it didn't colour the part where the legend overlaps the fieldset.