resize - Expanding/contracting columns with browser (ASP.Net) -

I'm trying to complete something like this, where you show images in many columns, but as You change your shape Browser, Column (D) will look like so that you can see it on the screen.

How can I do this (link, etc.)?

Thank you!

PS: Keep in mind that I am quite ASP.NET noob

Here is a link to the tutorial.