Pen Settings

HTML

CSS

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

+ add another resource

JavaScript

Babel is required to process package imports. If you need a different preprocessor remove all packages first.

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

+ add another resource

Behavior

Save Automatically?

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

Format on Save

If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

Want to change your Syntax Highlighting theme, Fonts and more?

Visit your global Editor Settings.

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.

HTML

              
                <div id="page-wrapper">
    
    <h1>Page Visibility API Demo</h1>

    <video id="video" width="640" height="365" controls>
      <source src="http://demos.matt-west.com/page-visibility-demo/videos/mikethefrog.webm" type="video/webm">
      <source src="http://demos.matt-west.com/page-visibility-demo/videos/mikethefrog.ogv" type="video/ogv">
      <source src="http://demos.matt-west.com/page-visibility-demo/videos/mikethefrog.mp4" type="video/mp4">
      <p>
        Your browser doesn't support HTML5 video.
        <a href="videos/mikethefrog.mp4">Download</a> the video instead.
      </p>
    </video>

  </div>
              
            
!

CSS

              
                html {
  font-family: Helvetica, Arial, sans-serif;
  font-size: 100%;
  background: #333;
}

#page-wrapper {
  width: 640px;
  background: #FFF;
  padding: 1em;
  margin: 1em auto;
  min-height: 300px;
  border-top: 5px solid #69c773;
  box-shadow: 0 2px 10px rgba(0,0,0,0.8);
}

h1 {
  margin-top: 0;
}

video {
  max-width: 100%;
}

              
            
!

JS

              
                window.onload = function() {
  // Get the prefix for this browser.  
  var prefix = getPrefix();

  // Prefix the document properties/events we will be using.
  var hidden = getHiddenProperty(prefix);
  var visibilityState = getVisibilityStateProperty(prefix);
  var visibilityChangeEvent = getVisibilityEvent(prefix);

  // Variable to track if the video was playing when the page visibility changed.
  var wasPlaying = false;

  // Get a reference to the video.
  var video = document.getElementById('video');

  // Listen for the visibilitychange event.
  document.addEventListener(visibilityChangeEvent, function(e) {
    
    // If the document is hidden we want to pause the video.
    if (document[hidden]) {
      // Check to see if the video is playing
      if (video.paused == false) {
        // Set the wasPlaying flag to true.
        wasPlaying = true;

        // Pause the video.
        video.pause();
      } else {
        // Make sure the wasPlaying is set to false if the video was paused.
        wasPlaying = false;
      }
    } else {
      // If the video was playing before we lost visibility, restart it.
      if (wasPlaying) {
        // Play the video.
        video.play();
      }
    }
  });

}

// Get the prefix for this browser.
function getPrefix() {
  // Check to see if the browser supports the unprefixed property.
  if ('hidden' in document) {
    // No prefix needed, return null.
    return null;
  }

  // Loop through all the possible prefixes.
  var prefixes = ['moz', 'ms', 'o', 'webkit'];

  for (var i = 0; i < prefixes.length; i++) {
    var testPrefix = prefixes[i] + 'Hidden';
    if (testPrefix in document) {
      return prefixes[i];
    }
  }

  // The API must not be supported in this browser.
  return null;
}

// Prefix the hidden property.
function getHiddenProperty(prefix) {
  if (prefix) {
    return prefix + 'Hidden';
  } else {
    return 'hidden';
  }
}

// Prefix the visbilityState property.
function getVisibilityStateProperty(prefix) {
  if (prefix) {
    return prefix + 'VisibilityState';
  } else {
    return 'visibilityState';
  }
}

// Prefix the visibilitychange event.
function getVisibilityEvent(prefix) {
  if (prefix) {
    return prefix + 'visibilitychange';
  } else {
    return 'visibilitychange';
  }
}

              
            
!
999px

Console