Slopes and intercept from (u−r)–μ_u fits. Interpolated slopes (left axis) and intercepts (right axis) obtained from linear fits for all 14 bins of A_FUV (Fig. D.1), as a function of A_FUV. The left axis represents slopes (purple full diamonds), and the right axis represents intercepts (red full circles). Linear fits and associated fitted parameters are presented using dashed-dotted lines for slopes and dashed lines for intercepts.