Tactical Training Excercises / Ejercicios de entrenamiento táctico

Hello. Could someone tell me what the green thumb up and the red thumb down mean in tactical exercises? Thank you! /
Hola. Podría alguien decirme qué significan el dedo pulgar verde hacia arriba y el dedo pulgar rojo hacia abajo en los ejercicios tácticos? Gracias!

It is a method to show your feedback to the site: thumb a puzzle up if you think it was a good puzzle and you liked it, thumb a puzzle down if you think it was a bad puzzle and needs to be removed.

ok. Thank you very much for your answer!