export class MyComponent {
  @ViewChild('message') 
  messageParagraph: ElementRef; 
  
  counter: 0;

  constructor(private renderer: Renderer2) {}

  onHereButtonClick() {
    if(this.counter > 10) {
       this.renderer.addClass(this.messageParagraph, "myclass");
    } else {
      this.counter += 1;
    }
  }
}