A two-piece cap assembly for closing an opening in a neck portion of the container is provided that includes a cap body having a top wall and a depending annular skirt for screw attachment to the neck portion of the container. A plug seal is attachable to the underside of the top wall of the cap body. The plug seal and the cap body are relatively rotatably coupled for independent rotation of the cap body with respect to the plug seal upon attachment and detachment of the cap to the neck portion of the container.