Calculate the triple integral of $z^2$ limited by the functions $z=0, x^2+z=1, y^2+z=1$

Question

Calculate $$\int\int\int_D z^2 dV $$ limited by the functions $$z=0 $$ $$ x^2+z=1; $$$$y^2+z=1$$

I am getting lost on setting the limits of integration not sure how to put the upper limit of z if I were to use dz dy dx