Mobile site blue bar problem

[Tinkerball]

Having a bit of a problem with the mobile site and it only started last night as it was fine up till then, now I cant use it. The blue bar at the bottom is now half way up my screen and wont move, any threads below it wont scroll, just the small bits above! Cant figure out how to fix it or what has changed?

[Tinkerball]

Back to normal now, no idea what caused that!