The invention relates to a closing system for a container to be held with a single hand. The closing system includes a cap having a skirt and a transversal wall provided with an access port, and a cover substantially parallel to the cap and with a guiding member intended to be used by a user to manipulate the cover. A hinge allows a planar rotation of the cover regarding the cap from a first position to close the access port to a second position to access the access port.
