Are front line ups permissible? Would it fall under qaza' or tashabbuh?
بِسْمِ اللهِ الرَّحْمنِ الرَّحِيْم
In the name of Allah, the Most Gracious, the Most Merciful
Qaza’ is defined as shaving some of the head (the amount of three fingers) and leaving the rest. This can be either various spots on the head or one portion on the head. Having this kind of hair cut is disliked due to the Qaza’: deforming the creation of Allah from its natural look or it being the hairstyle of the Jews.
Tashabbuh is to imitate a person or group of people due to having respect, love or fear of them.
Tapers, most fades (where there is no shaved part for more than the amount of three fingers), or line ups do not come in the category of qaza’. But if a person does any of these with the intent of following or imitating someone famous or a player, then it would be considered tashbbuh. It is prohibited to imitate anyone that has non-Islamic conduct or is known for their evil actions.
Only Allah knows best
Written by Maulana Shadman Ahmed
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham
 Muḥammad Amīn `Ibn ’Abidīn, Radd al-Muḥtār ’Alā al-Durr al-Mukhtār, Vol. 6. Pg.407. (Dār al-Fikr, 1252H).
 Al-Nawwawī, Sharḥ Al-Nawwawī ‘alā Muslim. Vol. 14. Pg. 104. Dār `Iḥyā al-Turāth.