Bottom: portion of 1D X-shooter spectrum around the C IV emission line, median-smoothed using a 5-pixel sliding window for presentation purposes (black, with 1σ error level in green). The inset shows an unsmoothed zoom-in on the C IV absorption, with the blue region highlighting the residual emission. The best-fit model is shown by the red solid line and the individual Gaussians as red dotted lines. The downwards arrow indicates the systemic redshift. Top: 2D spectrum in the region featuring the C IV absorption line as well as residual C IV emission in the trough.