CSS page SOMETIMES break

[iasseo]

This is a strange problem... I'm fairly new to CSS, but managed to build a fairly complex layout. Looks great on all platforms, problem is though that SOMETIMES, but only SOMETIMES it breaks (the layout goes out of whack) - but on refresh it goes back to normal.... it happens a lot - check it out for your selves: www.thancfoundation.org - refresh a bunch of times until it breaks.... any ideas about how to fix will be highly appreciated.

[ReFredzRate]

Now that's weird. If it works, it works, but your page doesn't somehow. Took my a while to try to figure stuff out, but I don't see any mistakes in the source either.... I'm sorry, I'm puzzled.