Special and Visual Effects : Inception-smaller effects?

Inception-smaller effects?

Hey everyone,

There's two effects that I haven't been able to find any information about. They are in the "bridge scene" when Ariadne is first playing around:

The first effect where she makes the flat platform rise into a set of stairs and the other one where she pulls the mirror-doors together to form the bridge. Anyone know how they did that or of any article that talks about it? I wonder how much visual and practical effects went into each.