Cladding of ceiling edge / staircase opening gallery

The area of the raw ceiling (concrete) and the area of the screed are to be covered.

I would probably have pulled up the raw ceiling at the edge of the hole and also framed in the screed (and either also the covering, or if these are tiles and especially the same as in the floor below, incorporated them into the edge). How did you solve it with the stairwell opening?

... can you take a photo? Also gladly via PM. Thanks

Take this one. When I am at home, it is dark.