Stratification of the pressure p, energy generation rate per unit volume ρε_nuc, opacity κ, and specific entropy s in the MESA model (thick grey lines) and in the SLH model at t = 0 (thin coloured lines). The profiles of p and ρε_nuc are normalised such that their maximum values are unity. The entropy of the convective core is set to 0. The jump in ρε_nuc at the boundary of the fully-mixed core is caused by a slight change in chemical composition, which is neglected in the SLH model.