Swap CSS class on the basis of Scroll Position with Javascript

Question

I\'m looking to re-create the Apple Store shopping cart sidebar.

http://store.apple.com/us/configure/MB535LL/A?mco=MTA4MTg3NTQ

It is similar to \"position:

Answer 1

This working in FF3.5!

 This is a banner1


    this is main div


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