import { Component , OnInit , OnDestroy } from '@angular/core' ; @ Component ( { selector : 'app-starter' , templateUrl : './starter.component.html' , styleUrls : [ './starter.component.scss' ] } ) export class StarterComponent implements OnInit , OnDestroy { body : HTMLBodyElement = document . getElementsByTagName ( 'body' ) [ 0 ] ; constructor ( ) { } ngOnInit ( ) { this . body . classList . add ( 'sidebar-mini' ) ; } ngOnDestroy ( ) { this . body . classList . remove ( 'sidebar-mini' ) ; } }