If the current page has been updated with your new code then I'm afraid its not working.
You seem to have just adjusted it fit the screen size you happen to be viewing at and should you open or close the window the menu will be misplaced which means 99% of your visitors will see it in the wrong place. (The original menu worked properly only if your page was aligned left because the offset was taken from the viewport and not the page width itself.)
I believe the solution is somewhere in the details that I mentioned before because the positioning of the menu was perfect locally and at any screen resolution. However I will have to have an another look and see if I can work out why the styling was lost.