Change theme dynamically without page refresh in ASP.NET

You must have noticed one link in yahoo.com, msn.com or other popular websites named "Page Options". When you click this link you get a popup displaying different small several color icons. After clicking one of these icons your page theme changes without entire page refresh. Now you are able to see the same page wit开发者_如何学Ch different look and feel.

How does it happen and what it takes to do it? Is this possible in ASP.NET? If yes, how to do it? Show me some syntax.

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Here is an example of how to change CSS stylesheets on the fly using jQuery.