We like our rhymes in Spanish (much like ‘easy peasy’ or ‘whatever Trevor!’ in English) and here we’re congratulating our friend Maribel on the amazing quality of something. (Nivel =‘level’, so we’re literally saying that’s something’s of the highest level of quality).
-Me he comprado una casa de 7 dormitorios en Hampstead.
-¿En serio? ¡Qué nivel, Maribel!