Wall that pops out of the ground

Hello, I've never done redstone before. I'd like to ask for help with a small project I'm trying to make in my friend server.

All I'm trying to do is make a 2 x 2 block wall pop out of the ground when I pull a lever, and move it back into the ground when I pull it again. Specifically I want the wall to be magma blocks like so.

I followed tutorials and can get 1 block to move in and out of the ground, but not more than that. I could really use some help if this is possible.