Color–color diagram of the synthetic WD+MS PCEBs obtained using our Monte Carlo simulator when our reference model (α_CE = 1.0, λ = 0.5, and n(q) = 1) is employed. Systems containing He WDs are represented using black dots, while blue dots correspond to systems with C/O or O/Ne WDs. The observed WD+MS PCEB systems are displayed using red dots. The color selection criteria are shown using red lines (Sect. 3.1). (Color version online.)