app.component.html

 <div class="buttons">
        <div class="round-button">
            <button appRight class="sergent" [rights]="'STUDENT'" (click)="explose($event)">STUDENT ONLY</button>
        </div>
        <div class="round-button">
            <button appRight class="both" [rights]="'STUDENT,INSTRUCTOR'" (click)="explose($event)">STUDENT & INSTRUCTOR</button>
        </div>

        <div class="round-button">
            <button appRight class="general" [rights]="'HEAD OF DEPARTMENT'" (click)="explose($event)">HEAD OF DEPARTMENT ONLY</button>
        </div>