Toy model of the spectral energy distribution of thermal emission produced by an accretion flow around an |$M=10^7 M_\odot$| binary with mass ratio |$q=0.01$|⁠. The model assumes that the three components of the accretion flow: inner disc (green), secondary disc (blue), and outer disc (red) can each be characterized as a steady-state |$\alpha$|-disc, with radial temperature profile consistent with equation (3).