Image (with absolute) not displayed right

Hi all,

I've got this website which has 2 backgrounds of ipads, post-it's etc (they random appear).
They are set with an position absolute, and they work fine on my PC. Image:

Now when I check it on a tablet or phone, it shows THIS:

Notice that they change randomly with a refresh, but the position of that one isnt good. It should be on the right side of my page and not in the middle.

Any help ?

URL: http://slice.prelicious.nl/poelman