A seat includes a seat-bottom frame, a seat-back frame rotatable relative to the seat-bottom frame between a forward position and a rearward position, and a first wedge and a second wedge on opposite side of the seat-back frame. The first wedge extends from the seat-back frame in the forward position to the seat-bottom frame, and the second wedge extends from the seat-back frame in the rearward position to the seat-bottom frame.