Left panel: nebular (blue) and stellar (black) FUV to NIR spectra. In total 124 lines from H II regions are taken into account. The nebular continuum takes into account free-free, free-bound, and two-photon processes. The lines are modelled from an improved version of the CLOUDY templates computed in Inoue (2011). Here the electron density is set to 100 cm⁻³, the metallicity Z = 0.02, and the ionisation parameter logU = −2. Both f_esc and f_dust are set to 0. The stellar emission is computed with the sfh2exp (t₁ = 13000 Myr, τ₁ = 7000 Myr, t₂ = 25 Myr, τ₂ = 50 Myr, and f = 0.1) and bc03 (Salpeter 1955; IMF and Z = 0.02) modules. Right panel: zoom in the 460 nm–740 nm range. At this scale we can see the line width due to gas motions. Here the line width is set to 300 km s⁻¹.