Pen Settings



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


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


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.


                <div class="container">  
  <div class="row">
    <div class="column">
      <div class="my-content"></div>
    <div class="column">
      <div class="my-content"></div>
    <div class="column">
      <div class="my-content"></div>

<div>Column width: <span id="output"></span>px</div>


                .column {
  float: left;
  box-sizing: border-box;
  width: 33.3333333%;
  padding: 0 4px;

.container {
  padding: 8px 3%;
  background-color: gray;

.row {
  margin-left: -8px;
  margin-right: -8px;
  overflow: hidden;

.my-content {
  height: 40px;
  background-color: rgb(220, 220, 220);


                var HAS_COMPUTED_STYLE = !!window.getComputedStyle;
var getStyles = window.getComputedStyle || function() {};

    return false;

  var parent = document.body || document.documentElement;
  var e = document.createElement('div'); = 'width:10px;padding:2px;' +

  var width = getStyles(e, null).width;
  var ret = width === '10px';


  return ret;

 * Retrieve the computed style for an element, parsed as a float.
 * @param {Element} element Element to get style for.
 * @param {string} style Style property.
 * @param {CSSStyleDeclaration} [styles] Optionally include clean styles to
 *     use instead of asking for them again.
 * @return {number} The parsed computed value or zero if that fails because IE
 *     will return 'auto' when the element doesn't have margins instead of
 *     the computed style.
var getNumberStyle = function(element, style, styles) {
    styles = styles || getStyles(element, null);
    var value = getFloat(styles[style]);

    // Support IE<=11 and W3C spec.
    if (!COMPUTED_SIZE_INCLUDES_PADDING && style === 'width') {
      value += getFloat(styles.paddingLeft) +
        getFloat(styles.paddingRight) +
        getFloat(styles.borderLeftWidth) +
    } else if (!COMPUTED_SIZE_INCLUDES_PADDING && style === 'height') {
      value += getFloat(styles.paddingTop) +
        getFloat(styles.paddingBottom) +
        getFloat(styles.borderTopWidth) +

    return value;
  } else {
    return getFloat($(element).css(style));

var isNumber = function(n) {
	return !isNaN(parseFloat(n)) && isFinite(n);

var getFloat = function(value) {
  value = parseFloat(value);
  return isNumber(value) ? value : 0

function showWidth() {
  var output = document.querySelector('#output');
  var column = document.querySelector('.column');
  output.textContent = getNumberStyle(column, 'width');

window.addEventListener('resize', showWidth);