How to create a dynamic navigation bar which follows you when you reach certain location

Question

I want to create a navigation bar similar to this site\'s:

http://www.mysupermarket.co.uk/#/shelves/top_offers_in_asda.html

Can anyone tell me how to create

Answer 1

if you want you could just set the z-index to be a specific No. and that should work.

example z-index:100;