[Angular] Use Angular’s @HostBinding and :host(...) to add styling to the component itself

One thing that we can do is to add styles directly to HTML elements that live within our component. However, in this lesson we see that style classes added to your template HTML within your component get applied to an inner <div> and not your component host. We will learn how to use :host(...) and @HostBinding to add styling directly to the component host itself.

import { Component, HostBinding } from '@angular/core';

@Component({
  selector: 'host-styling',
  template: `
    <div>
      I'm a div that wants to be styled
      <button (click)="redFont = !redFont">toggle</button>
    </div>
  `,
  styles: [
    `
      /* Apply this style if .yellow-style is added to the component tag itself */
      :host {
        background-color: yellow;
        display:block;
      }

      :host(.red-font) {
        color: red;
      }
    `
  ]
})
export class HostStylingComponent {
  @HostBinding ('class.red-font') redFont = true;

}

We can use :host(<class-name>) with @HostBinding, it will add .red-font class to the host element based on condition.