app.component.html

  <mat-toolbar color="primary">
    <mat-toolbar-row>
      <span><a href=""><img src="/assets/THD-Logo.png" height="50"></a> THD App</span>
    </mat-toolbar-row>
    <mat-toolbar-row class="flexSpaceBetween">
      <button mat-raised-button routerLink="/navigation">Navigation</button>
      <button mat-raised-button routerLink="/rooms">Rooms</button>
      <button mat-raised-button routerLink="/international">International</button>
      <button mat-raised-button routerLink="/login">Login</button>
  </mat-toolbar-row>
  </mat-toolbar>

<div class="main">
  <router-outlet></router-outlet>
</div>