I am a current Year 12 in IB, and I am very confused (since I recently moved class)

Is the definition of Lattice Enthalpy (for IB) :solid forming from gaseous ions or gaseous ions forming solid?

and The Born Haber Cycle for NaCl. I've been taught two different versions! one version had the lattice enthalpy as negative. Na+ + Cl- with arrow down to NaCl (s) while the other version is NaCl(s) arrow pointing down to Na+ + Cl- and the lattice enthalpy is positive.

which one is the right answer???? which is the right way ? (at least for IB)