Just a guess that there might be screws under the black rubber pads.
I'm typing on mine atm, but I don't want to pull it apart.
If you push down really hard on the black rubber pads, it feels like the middle has a hole under it.
You can try carefuly peeling one up, but don't remove it all the way. When you get it half way it should be clear whether there's a screw hole underneath or not.