What do you mean when you say it didn't work? What did you try, and what
did it do?

You should be able to identify the markup that makes up the field; just dig
into the rendered HTML with the View Source command in the browser. At that
point you can use a local stylesheet to either override one of the relevant
classes (if you want all fields on the page to look different) or add an
ID-based style (to alter the appearance of only one field at a time).