Active Tab CSS

Hi to all. I use wordpress and had created a form with tabs within a page post. Unfortunately I don’t know how to highlight the current form tab with css.

This is the div from the form:

<div id="form_type">
						<p>
						<a href="#" id="change_log" class="change_type">Submit 1</a>
						<a href="#" id="change_photo" class="change_type">Submit 2</a>
						<a href="#" id="change_video" class="change_type">Submit 3</a>
						</p>
					</div>

A little help will be very appreciated!
Thanks.