Observed Mg II h and k spectrum, with the continuum windows used in this study (vertical dashed lines). The continuum windows are located far from the wings of the strong resonant Mg II lines at 2796 and 2803 Å. Bottom: Magnified views of the selected continuum regions. The blue spectrum corresponds to the time when the continuum emission was enhanced, while the orange spectrum represents the post-enhancement period during the flare’s impulsive phase.