A lid that blocks an opening of a housing of a computer includes an inner lid, an outer lid, and a water stop member. The inner lid includes an engagement hole at an end of the inner lid on a side close to a hinge axis. The housing includes an engagement projection that is engaged with the engagement hole when the inner lid is rotationally moved until the inner lid faces a bottom surface. The outer lid includes a right protrusion at an end of the outer lid on a side far from the hinge axis. The housing includes an engagement recess that is engaged with the right protrusion when the outer lid is slid away from the hinge axis.