Theme suddenly disappeared

Its done this once before, the forum has only been up a fortnight! The forum theme background has just disappeared in the space of a few seconds and I havent touched a thing in admin. It should be the vistaplain skin with customised bits.

http://thecockerforum.forumotion.co.uk/forum.htm (spaniel forum- nothing dodgy!)

Any ideas? Last time I just reinstalled my theme but it took ages to get everything back to normal. Will it fix itself maybe?

I don't see a problem. You might of gotten a white screen which means your forum is being backed up.

me neither.i dont see a problem.

It fixed itself pretty fast but still don't understand what happened. Will take a screenshot if there's another time.