Rotatable car seat and base

A car seat, comprising:

• a base including a receiving portion;
• a seat shell including a seat bottom having a top surface and a lower portion forming a convex surface, the seat bottom lower portion interfacing with the receiving portion of the base, wherein the seat shell is rotatable with respect to the base such that the seat shell is selectively positionable between at least a rearward-facing position and a forward-facing position;
• and
• a recline mechanism between the seat bottom top surface and the seat bottom lower portion, the recline mechanism configured to permit the seat shell to recline with respect to the base such that the seat shell is selectively reclinable between at least an upright position and at least one reclined position.