Describe in detail Parvana’s family’s apartment.

From the text:

They lived on the third floor of an apartment building. It had been hit in a rocket attack, and half of it was rubble.
The stairs were on the outside of the building, zigzagging back and forth on their way up. They had been damaged by the bomb, and didn't quite meet in places. Only some parts of the staircase had a railing. "Never rely on the railing," Father told Parvana over and over.