Light curve fitting results of the CSS V band (left, red symbols) and the ZTF g and r bands (right, blue and green symbols). First row: Direct sinusoidal fitting results. In the top panel, the solid red and dashed orange lines show the best-fitting results and corresponding 5σ confidence bands from a sinusoidal function plus a fifth-degree polynomial component. The dashed purple lines represent the polynomial components, and the solid purple lines represent the determined sinusoidal components. Second row: Phase-folded fitting results. In the top panel, the solid red and dashed orange lines show the best-fitting results and the corresponding 5σ confidence bands. The bottom panels of each row display the corresponding residuals (light curves minus the best-fitting results), with solid red lines showing residuals = 0.