How do I center the main div? - jKit Prallax Effect

Here's a website I'm working on: www.rill-studio.com/test/test.html

As you can see main title "Let's be social again" isn't properly centred when the website loads in initially but it centres when you start scrolling and stays in a correct position afterwards.

Could you suggest a good fix for that? I'm loosing my mind here.