Top panel: schematic representation of the orbit of WASP-76 b. The orbital phases covered in this study with GIARPS are colour-coded according to observing night. Bottom panel: S/N averaged over orders as a function of the orbital phase for nights in emission. The markers’ colour is proportional to the airmass. The exposures with higher S/N are from HARPS-N, while those with lower S/N are from GIANO-B.