botão de íons transparente
<ion-button (click)="onClick()" fill="clear">
<ion-icon slot="icon-only" name="home"></ion-icon>
</ion-button>
Mobile Star
<ion-button (click)="onClick()" fill="clear">
<ion-icon slot="icon-only" name="home"></ion-icon>
</ion-button>
<ion-button color="primary" fill="outline">Primary</ion-button>
<ion-button class="button-long" expand="full" (click)="login()">Login</ion-button>