Two- and one-parameter marginalised constraints obtained from a joint three-parameter analysis of (w₀, w_a, Ω_m) for the full Euclid-like mask, including different combinations of covariance contributions: Gaussian (G), super-sample (SS), and connected non-Gaussian (CNG). Shape noise is included, following Eq. (9). The constraints in each panel have been obtained by marginalising over one or two parameters in the joint three-parameter posterior; for example, the panel marked ‘Marg. w_a, Ω_m’ has been marginalised over w_a and Ω_m. All other parameters are held fixed. Only the 1 and 3 σ confidence regions are marked.