A molded article includes an exterior surface and an opposite interior surface spaced apart by a thickness of the molded article and defining, on opposite sides of the molded article, an inner panel, a main body, and a contoured portion. The contoured portion extends between and interconnects the inner panel and the main body so as to surround the inner panel and be surrounded by the main body. The contoured portion includes contoured corner segments and contoured intermediate segments extending between respective pairs of the contoured corner segments lengthwise. The thickness of the molded article includes a first maximum thickness at the contoured intermediate segments measured from the exterior surface to a closest point of the interior surface, and a second maximum thickness at the contoured corner segments measured from the exterior surface to a closest point of the interior surface that is less than the first maximum thickness.