What is the ruling on the "kadash" (messy/afro-like) hairstyle for young men, and is it considered qaza' (shaving parts of the head and leaving other parts) or imitating disbelievers, even though those who wear it consider it merely a fashion and not against Islamic law?

There is no harm in styling hair in any way for adornment, provided that it does not involve an impermissible imitation of disbelievers or transgressors in what is exclusive to them, or men imitating women. The specific criterion for impermissible imitation must be observed. Furthermore, attention must be paid to the seriousness of extravagance in adornment, especially for men, due to the Prophet, peace and blessings be upon him, saying: "The Messenger of Allah, peace and blessings be upon him, forbade combing one's hair except infrequently," and his saying: "Indeed, humility in dress is part of faith," and his prohibition to Mu'adh: "Beware of a life of luxury, for the servants of Allah are not those who live luxuriously."