What is this toy and where can I get it?

Saw this really cool toy, but I don’t know what it’s called, so I can’t google it. It’s flat colored translucent plastic shapes, just under a quarter inch thick. They have magnets in all edges, so you can put them together and build all kinds of things. There are squares (about 2 and a half inches across), equilateral triangles, isosceles triangles, maybe others – I didn’t see the others. What are these things and where can I get them?