Highlighting special characters in math environment

[Kauê da Silva Sena]

Hi!
In this section
<https://www.gnu.org/software/auctex/manual/auctex.html#User_002ddefined-keyword-classes>
of the AUCTeX manual, it is described how one could customize the
highlighting of commands started with a backslash. I'd like, however, to
give special highlighting to certain unicode symbols when they are inside a
math environment. For example, =,+,×,⊆, ⊂, ∩, ↦, →,≥,≤,≅,≃,∀,∃,∈,∑. I use
those with XeLaTeX and have a method for directly inputting them.
Thank you for any help,
Kauê