Expanding/contracting columns with browser (ASP.Net)

I'm trying to accomplish something like this (http://picturegroup.com) , where you have images displayed in se开发者_运维问答veral columns, but as you resize your browser, columns will (dis)appear so to fit what you can see on the screen.

Any ideas on how can I do this (links, etc)?

Thanks!

PS: Bear in mind that I'm quite a ASP.Net noob

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The site uses a css property called float.

Here is a link to a tutorial

http://css.maxdesign.com.au/floatutorial/