<!DOCTYPE html>
<html>

  <head>
    <title>ngx-bootstrap plunkr</title>
    <!-- Load common libraries -->
    <script src="https://cdnjs.cloudflare.com/ajax/libs/typescript/2.1.6/typescript.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/core-js/2.4.1/core.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/zone.js/0.7.2/zone.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.47/system.js"></script>
    <!-- Configure SystemJS -->
    <script src="systemjs.config.js"></script>
    <script>
      System
        .import('main.ts')
        .catch(console.error.bind(console));
    </script>
    <link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" />
    <style>body { font-family: Roboto, Arial, sans-serif; margin: 0 }</style>
  </head>

  <body>
    <ngx-app>Loading ngx-bootstrap...</ngx-app>
    <!--
Copyright 2016 Google Inc. All Rights Reserved.
Use of this source code is governed by an MIT-style license that
can be found in the LICENSE file at http://angular.io/license
-->
  </body>

</html>
import { Component, OnInit } from '@angular/core';
@Component({
  selector: 'ngx-app',
  templateUrl: 'app.component.html',
  styleUrls: ['styling.css']
})
export class AppComponent {
customClass: string = 'customClass';
  isFirstOpen: boolean = true;
}
<accordion>
  <accordion-group heading="Static Header, initially expanded"
                   [panelClass]="customClass"
                   [isOpen]="isFirstOpen">
    This content is straight in the template.
  </accordion-group>
  <accordion-group heading="Content 1">
    <p>accordion 1</p>
  </accordion-group>
  <accordion-group heading="Content 2" panelClass="customClass">
    <p>accordion 2</p>
  </accordion-group>
</accordion>
import {platformBrowserDynamic} from '@angular/platform-browser-dynamic';
import {BrowserModule} from '@angular/platform-browser';
import {NgModule} from '@angular/core';
import {CommonModule} from '@angular/common';
import {FormsModule} from '@angular/forms';
import {AppComponent} from './app.component';
import {AccordionModule} from 'ngx-bootstrap'


@NgModule({
  imports: [
    BrowserModule,
    CommonModule,
    FormsModule,
    AccordionModule.forRoot()
  ],

  declarations: [AppComponent],
  bootstrap: [AppComponent]
})
export class PlunkerNgxModule {}

platformBrowserDynamic().bootstrapModule(PlunkerNgxModule);

/*
 Copyright 2016 Google Inc. All Rights Reserved.
 Use of this source code is governed by an MIT-style license that
 can be found in the LICENSE file at http://angular.io/license
 */
/** Add Transpiler for Typescript */
System.config({
  transpiler: 'typescript',
  typescriptOptions: {
    emitDecoratorMetadata: true
  },
  packages: {
    '.': {
      defaultExtension: 'ts'
    },
    'vendor': {
      defaultExtension: 'js'
    }
  }
});

System.config({
  map: {
    'main': 'main.js',
    
    // Angular specific mappings.
    '@angular/core': 'https://unpkg.com/@angular/core/bundles/core.umd.js',
    '@angular/common': 'https://unpkg.com/@angular/common/bundles/common.umd.js',
    '@angular/compiler': 'https://unpkg.com/@angular/compiler/bundles/compiler.umd.js',
    '@angular/forms': 'https://unpkg.com/@angular/forms/bundles/forms.umd.js',
    '@angular/platform-browser': 'https://unpkg.com/@angular/platform-browser/bundles/platform-browser.umd.js',
    '@angular/platform-browser-dynamic': 'https://unpkg.com/@angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
    
    // Third party libraries
    'tslib': 'https://unpkg.com/tslib@1.7.1',
    'rxjs': 'https://unpkg.com/rxjs',
    'ngx-bootstrap': 'https://unpkg.com/ngx-bootstrap/bundles/ngx-bootstrap.umd.min.js'
  },
  packages: {
    // Thirdparty barrels.
    'rxjs': { main: 'index' },
  }
});

/*
 Copyright 2016 Google Inc. All Rights Reserved.
 Use of this source code is governed by an MIT-style license that
 can be found in the LICENSE file at http://angular.io/license
 */
::ng-deep .card.customClass,
::ng-deep .card.customClass .card-header,
::ng-deep .panel.customClass {
  background-color: #5bc0de;
  color: #fff;
}
::ng-deep .panel.customClass .panel-body {
  background-color: #337aa7;
}