How to fix main navigation on top when scrolling down

[darksuyan]

First, Merry Christmas to allI want to fix my top navigation menu bar on top when scrolling down like : csschopper.comthis happen by \[code\]position: fixed;\[/code\] css property but when i put it in css menu will be fixed at top. this will require some javascript code but I don't know what exactly the code is. also when someone scroll down i also want to display small logo beside the menu like csschopper.comThanks in advance.