Luminosity-weighted mean age (left panels) and mean stellar metallicity (right panels) as a function of stellar mass and of SSFR for LEGA-C galaxies at z ≈ 0.7. Upper panels: Data points colour-coded by SSFR after applying LOESS-smoothing. The black vectors in the lower right corner are proportional to the partial correlation coefficients computed as in Scholz-Díaz et al. (2024), and the red vector indicates the direction of maximal increase of SSFR. The grey vectors correspond to a reference correlation coefficient of 0.7. Middle panels: Q galaxies (circles) and SF galaxies (stars), colour-coded by their SSFR, without smoothing. The filled symbols highlight galaxies in the golden subsample. The filled squares show the median age and median metallicity in bins of stellar mass 0.2 dex wide and with at least 5 galaxies (grey for the weighted silver sample, black for the non-weighted golden galaxies). The error bars indicate the 16–84 percentile range of each distribution (errors on the median are smaller). The median age-mass trends are fit with a linear relation (Eq. (2)), while the median metallicity–mass trends are fit with the functional form as in Eq. (3). The solid grey lines show the fit to the silver median relations, with extrapolation shown by the dashed lines. Bottom panels: Direct comparison of the volume and completeness-weighted median relations for Q (magenta) and SF (blue) galaxies in the silver sample.