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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

<template id="dialog-template">
    .wrapper {
      opacity: 0;
      transition: visibility 0s, opacity 0.25s ease-in;
    .wrapper:not(.open) {
      visibility: hidden;
    } {
      align-items: center;
      display: flex;
      justify-content: center;
      height: 100vh;
      position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
      opacity: 1;
      visibility: visible;
    .overlay {
      background: rgba(0, 0, 0, 0.8);
      height: 100%;
      position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;
      width: 100%;
    .dialog {
      background: #ffffff;
      max-width: 600px;
      padding: 1rem;
      position: fixed;
    button {
      all: unset;
      cursor: pointer;
      font-size: 1.25rem;
      position: absolute;
        top: 1rem;
        right: 1rem;
    button:focus {
      border: 2px solid blue;
  <div class="wrapper">
  <div class="overlay"></div>
    <div class="dialog" role="dialog" aria-labelledby="title" aria-describedby="content">
      <button class="close" aria-label="Close">✖️</button>
      <h1 id="title">Hello world</h1>
      <div id="content" class="content">
        <p>This is content in the body of our modal</p>


<button id="launch-dialog">Launch dialog</button>
              #launch-dialog {
  background: tomato;
  border-radius: 4px;
  color: #fff;
  font-family: Helvetica, Arial, sans-serif;
  padding: 0.5rem 1rem;
  position: static;
              'use strict';

class OneDialog extends HTMLElement {
  static get observedAttributes() {
    return ['open'];
  constructor() {
    this.close = this.close.bind(this);
  attributeChangedCallback(attrName, oldValue, newValue) {
    if (oldValue !== newValue) {
      this[attrName] = this.hasAttribute(attrName);
  connectedCallback() {
    const template = document.getElementById('dialog-template');
    const node = document.importNode(template.content, true);
    this.querySelector('button').addEventListener('click', this.close);
    this.querySelector('.overlay').addEventListener('click', this.close); =;
  disconnectedCallback() {
    this.querySelector('button').removeEventListener('click', this.close);
    this.querySelector('.overlay').removeEventListener('click', this.close);
  get open() {
    return this.hasAttribute('open');
set open(isOpen) {
    this.querySelector('.wrapper').classList.toggle('open', isOpen);
    this.querySelector('.wrapper').setAttribute('aria-hidden', !isOpen);
    if (isOpen) {
      this._wasFocused = document.activeElement;
      this.setAttribute('open', '');
      document.addEventListener('keydown', this._watchEscape);
    } else {
      this._wasFocused && this._wasFocused.focus && this._wasFocused.focus();
      document.removeEventListener('keydown', this._watchEscape);
  close() {
    if ( !== false) { = false;
    const closeEvent = new CustomEvent('dialog-closed');
  _watchEscape(event) {
    if (event.key === 'Escape') {

customElements.define('one-dialog', OneDialog);

const button = document.getElementById('launch-dialog');
button.addEventListener('click', () => {
  document.querySelector('one-dialog').open = true;
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