Swinging lamp

so i added a swinging lamp, if only because I wanted to learn how to do the animation.

Anyway, the most annoying thing was when i decided to move it between the two trains and doing so wrecked the vertical positioning of the other divs, i'd suggest changing from position:relative to position:absolute, but i'm not sure about any other side effects.

I was also confused by the ease option on the animation, but settled with ease-in-out as it seems to give the closest to simple pendulumn motion... 

anyway, just thought you'd like to see :)