How to make use of it:

1. Load the required jQuery and handlebars.js libraries within the HTML web page.

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/handlebars.js/4.0.11/handlebars.min.js"></script>

2. Load the Goodpopup plugin’s JavaScript and Stylesheet within the web page.

<link href="jquery.goodpopup/css/style.min.css" rel="stylesheet">
<script src="jquery.goodpopup/js/script.min.js"></script>

3. Put your modal content within the <script> tag.

<script id="demo-popup" type="text/x-handlebars-template">
  <div class="popup">
    <h1 class="popup__header">Popup Title</h1>
  </div>
</script>
<script id="demo-popup" type="text/x-handlebars-template" data-is-prerendered="true" data-is-outer-click-closing="false">
  <img src="1.jpg" alt="">
</script>
<script id="demo-popup" type="text/x-handlebars-template" data-is-prerendered="true" data-is-iframe="true" data-key-code-for-closing="false">
  <iframe frameborder="0" allowtransparency="true" scrolling="no" src="1.html"></iframe>
</script>

4. Or create the modal content material in a DOM node.

<div class="template" id="demo-popup">
  Modal Content here
</div>

5. The JavaScript to open the modal windows.

$.goodpopup.getPopup("demo-popup").open();

6. Override the default options to customize the modal windows.

const myPopup = $.goodpopup.getPopup("demo-popup")
myPopup.setOptions({
  // is pre-rendered
  isPrerendered: false,
  // content is an iframe
  isIframe: false,
  // saves the content when hidden
  isDetachable: false,
  // closes the modal by clicking outside 
  isOuterClickClosing: true,
  // is full width
  isFullWidth: false,
  // shows close button
  hasCloseButton: true,
  // close the modal with ESC key
  keyCodeForClosing: [27],
  // forces closing
  forceClosing: {
    click: true,
    keydown: true,
    button: false
  },
  // Handlebars allows you to use an object with data for additional flexibility when rendering a template
  data: {}
})

7. Callback features.

myPopup.setOptions({
  callbackBeforeOpen: function() {},
  callbackAfterOpen: function() {},
  callbackBeforeClose: function() {},
  callbackAfterClose: function() {},
})

8. API strategies.

// open the modal
myPopup.open()
// close the modal
myPopup.close(true)
// detect if is rendered
myPopup.isRendered()
// detect if is hidden
myPopup.isHidden()
// set options
myPopup.setOptions({})
// get options
myPopup.getOptions()
// get content from the modal
myPopup.getPopupContent()
// get modal ID
myPopup.getPopupId()

See Demo And Download