fading between updates

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C#

ASP.NET

Javascript

Ajax

I was wondering what the best way to fade between postbacks in an update panel. Basically I highlight parts of a paragraph when you click a button. These changes are within an update panel and I was wondering if there was a good way to fade the changes over time (like a second fade) so that the changes don't just jump out and appear highlighted.

I imagine I'll need ajax or javascript but I'm kind of new to ajax and javascript so if you could kind of tell me what I need to know that would help me learn.