Density (left) and temperature (right) profiles of a 1 M_⊙ MS star of different models (see Table 1). The dashed and solid lines represent the 1D profiles generated by MESA and initialized (and subsequently relaxed for five dynamical timescales) in 3D in AREPO, respectively. They agree very well over most of the range, except close to the stellar surface because of smoothing during relaxation in AREPO. An older MS star (with lower H_c) has a denser and hotter core and a puffier outer layer than a younger MS star (with higher H_c).