Change Background color and text color dynamically.

Hi guys i have senario where i have to update the Theme color based on Users. each
User has his own theme Color Hex code.. which is store  in DataBase..
I Have Fetched the Theme Color code from the Database But  now the Challange is I want to Update those colors.. I don't know how i can  Pass those theme colors to the _Layout page.  I just want to update the those color once and it should work everywhere.. Any Suggestion guys!!!
(Please suggest according to the  ASP.NET MVC Core 2.2)