I had a similar problem. I wanted to be able to adjust the host style on certain components in a consistent way, but not all components (I am setting height and overflow). I used @HostBinding('style') and created a global constant. So each class I want to have this common style, I do this:
import { Component, HostBinding} from '@angular/core';
import { MAIN_CONTENT_HOST_STYLE} from '../../app.constants';
//Using HostBinding directly to set the Default style for main screen
@Component({
selector: 'app-my-component',
templateUrl: './my.component.html',
styleUrls: ['./my.component.css']
})
export class MyComponent {
@HostBinding('style') style = MAIN_CONTENT_HOST_STYLE;
}