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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.

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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.

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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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Code Indentation


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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.

              <input id="darkmode" type="checkbox"> <label for="darkmode">Dark Mode</label>

<h1>A minimal example</h1>

<p>Check the “dark mode” box above to switch the color scheme of the page. When picking colors, <a href="https://color.review/">make sure they’re high-contrast</a> so that people can read them. I find it easier to keep track of variables if they’re grouped alphabetically <em>and</em> conceptually, which is why I like <code>--colorBackground</code> and <code>--colorForeground</code>. It’s easy to keep all your color variables in one place and scan them quickly if you begin all of them with the common <code>--color</code> prefix.</p>
              :root {
  --colorBackground: white;
  --colorForeground: darkslategray;
  --colorLink: royalblue;
  --colorCode: crimson;

.dark {
  --colorBackground: black;
  --colorForeground: lightgray;
  --colorLink: cornflowerblue;
  --colorCode: lightpink;

body {
  background-color: var(--colorBackground);
  color: var(--colorForeground);

a {
  color: var(--colorLink);

code {
  color: var(--colorCode);
              document.querySelector('#darkmode').addEventListener('change', function(event){
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