Allowing style tag in TinyMCE editor

In cases i want to add individual styles for an element its easy i just add inline styles inside p tags, because _wp_add_global_attributes has style attribute….
but when i want to add <style> tag itslef to target/select multiple elements TinyMCE editor removes it entirely so got inside and got two filters tiny_mce_before_init but i don’t know how to add style tag to allowed tags array!!!!!!!