What is the specific uniform requirement for the libero?

The libero is required to wear a solid-colored uniform top that clearly distinguishes them from the rest of their teammates and from the opposing team. This specific uniform requirement is crucial as it helps officiate the game by making it immediately apparent who the libero is, especially since they have unique rules pertaining to their role on the court, such as the ability to substitute in and out more freely than other players and the restriction on attacking the ball above the net. A solid color ensures there is no confusion during play about the identity of the libero, which is pivotal for both the players and the officials enforcing the rules of the game.