Ionic list height in button ion item

Ionic Framework ionic-v3
1

dear all,

i have created an ion-list, i want to increase the height of the list items because some of the text is hiding because of the font size.
my current code is below

        <ion-item-divider color="light" text-center>topic1</ion-item-divider>
        <ion-list  class="my-ion-list" no-lines>
          <button ion-item   *ngFor="let item of items2" (click)="itemTapped($event, item)" text-right>
            {{item.TajweedLilOlama}}
          </button>
        </ion-list>
      </ion-item-group>

in the scss file of my page, i add below

.my-ion-list {
max-height: 400px;
}

but it is not increasing the height of the ionic list items.
can somebody help me with that please?
thank you.