Well, time to learn then
, what you need to research is DHTML, get yourself a copy of Sitepoint's "Modern Web Design uisng JavaScript & DOM" or Google for DHTML tutorial.
Seriously though you need to spend the time and understand fully what is happening within the browser as it will help you build better web sites. Any fool can load Dreamweaver or Photoshop and craft something that looks nice, what sets you apart is the ability to make the system do what you want.
Basically the whole web page is a large collection of objects, when you load the page it creates each of these objects (<P> <div> and so on), it then applies 1 or more style sheets to modify these objects (you can often see a page load then re-format itself as it applies the style sheet if the connection is slow).
All you need to do is select the object you want, hook in to it's event trigger (in this case when someone selects (focus event) it and then deselects it (blur event)) and then modify it's style attributes.