Create ButtonGroup with rounded corner in Angular ButtonGroup component

import { Component } from '@angular/core';

@Component({
    selector: 'app-root',
    template: `<!-- To render ButtonGroup. -->
               <div class='e-btn-group e-round-corner'>
                 <button ejs-button>HTML</button>
                 <button ejs-button>CSS</button>
                 <button ejs-button>Javascript</button>
               </div>`
})

export class AppComponent { }

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { ButtonModule } from '@syncfusion/ej2-angular-buttons';
import { AppComponent } from './app.component';
import { enableRipple } from '@syncfusion/ej2-base';

enableRipple(true);

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule,
        ButtonModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);