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.


                mixin card(color, title, text)
  article.card(style="--card-header-color:" + color)
    h2= title
    p= text

  h1 CSS Vars Demo
    label Columns
      input(type="range" data-prop="--main-columns" min="1" max="3" value="3")
    label Font size
      input(type="range" data-prop="--main-font-size" data-unit="px" min="8" max="16" value="12")

  +card("#FF998C", "Themes", "These buttons updates page color, but not card's")
    button.theme(data-prop="--root-background-color" value="#ccc") Light
    button.theme(data-prop="--root-background-color" value="#444") Dark
  +card("#FFEFE5", "Did you know?", "The markup was done using pug, which is a rich template engine for Node.js.")
  +card("#FFE16D", "Columns", "Change columns slider to change cards size πŸ“")
  +card("#D7FFAA", "Did you know?", "Every valid CSS stylesheet is a valid SCSS file with the same meaning.")
  +card("#9FE0FF", "Font size", "This other slider updates the font size of these cards 𝓐")
  +card("#A49EFF", "Did you know?", "ECMAScript is the β€œproper” name for the language commonly referred to as JavaScript")

  p Copyright &copy; 2018


                :root {
  --root-background-color: #ccc;
  --main-columns: 3;
  --main-font-size: 12px;
  --card-header-color: white;
  --card-body-color: white;
  --gutter: 8px;

body {
  background-color: var(--root-background-color);

header, footer {
  background: linear-gradient(to top, rgba(0, 0, 0, 0.4), rgba(0, 0, 0, 0.4)) var(--root-background-color);
  min-height: 60px;
  align-items: center;
  color: white;
  text-shadow: 1px 1px rgba(0,0,0,0.5), -1px 1px rgba(0,0,0,0.5), 1px -1px rgba(0,0,0,0.5), -1px -1px rgba(0,0,0,0.5);

header {
  padding: var(--gutter) calc(var(--gutter) * 4);
  h1 {
    display: inline-block;

.controls {
  float: right;
  display: inline-block;
  padding-top: 18px;
  label {
    display: block;

footer {
  display: flex;
  p {
    margin: 0 auto;

main {
  columns: var(--main-columns);
  font-size: var(--main-font-size);
  padding: var(--gutter) 0;

.card {
  background-color: var(--card-body-color);
  min-height: 120px;
  margin-bottom: var(--gutter);
  h2 {
    background-color: var(--card-header-color);
    margin: 0;
  h2, p {
    padding: var(--gutter) calc(var(--gutter) * 2);


                app = () => {
  const eventHandler = event =>,
      `${}${ || ''}`

    .forEach(input => input.addEventListener('input', eventHandler));

    .forEach(input => input.addEventListener('click', eventHandler));

window.addEventListener('load', app);