Upper row: 2D intensity maps for CI Tau at ALMA bands 3, 6, 7. The white bar in each panel shows the beam size. The white dotted lines mark the profile radial averaging intervals: 22.0 ± 5.3 (band 3), 22.0 ± 2.6 (band 6), 22.0 ± 6.6 (band 7). Lower row: CI Tau azimuthal brightness temperature profiles in ALMA band 3 (left), 6 (centre), 7 (right) shown in magenta, with the corresponding model profiles overplotted in blue. The blue curves are illustrative examples from the model grid that qualitatively reproduce the observed signature (not obtained from a formal best-fit procedure). The shaded areas show profile uncertainties. The grey dashed lines mark the minor axis.