I'm trying to let the users that visit my website change the size of text on it via a dropdown menu, or links or whatever. Like this page on the top right corner:
http://www.section508.gov/
I know if I want to change, text color for instance I could use this:
<a href="#" onClick="document.bgColor='yellow';">Yellow!</a>
but how can I change the size of all the text? Thanks!