How to change the class of one component from another in Angular 5?

Question

Angular

Let's say I have a navbar.component.ts component with html AND there is a second component aside.component.ts
<nav class='test'>Навигация</nav>

<aside>
<button>Кнопка</button>
</aside>

By clicking on the button in the aside component, the class in the navbar component should change, for example: class test to class test1. These components are neither children nor parent of each other.
The code is optional, just tell me which way to look.

Answer 1

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