Magnification pattern around the caustics (for the close-wide 3L1S model) and the light curve around the time of the source approach close to the planetary caustic induced by M₂. The small empty circle on the source trajectory represents the source position at the time of the source approach, at t_approach ~ 8581.7 in HJD′. The size of the circle is arbitrarily set and is not scaled to the source size.