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 includes JSX processing.

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

Packages

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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

              
                Enter your name: <input type="text" id="name"> <button id="save">Guardar</button>
              
            
!

CSS

              
                
              
            
!

JS

              
                // When the user clicks the element with id "save"...
document.getElementById('save').addEventListener("click", function(){
  
 
  // Get the name of the user. To do that, we read the DOM, search the node of the tree
  // with id "name" and get it's value. Store the value in the variable theName
  var theName = document.getElementById('name').value  

  // Once we have the name of the user, we create a new node for the tree that represents
  // the marquee tag using the createElement() method. This marquee tag will have no content, 
  // it will be empty, like <marquee></marquee>
  var marquee = document.createElement('marquee');

  // Using the createTextNode, we will create the content of the marquee
  var theTextOfTheMarquee = document.createTextNode('hello, ' + theName + '!');
  
  //Once we have the text, we will put it inside to marquee using the method appendChild() 
  //of the marquee
  marquee.appendChild(theTextOfTheMarquee);
  

  // At this point, we have the marquee with it's text inside but it is not 
  // visible in the web page yet. We have the tree that represents the page
  //   html
  //   |
  //    - body
  //      |
  //       - Enter your name
  //       - input id="name"
  //       - button id="save"
  //         |
  //          - Guardar 
  // But the node that represents the marquee is not in that tree. To make it visible,
  // we have to add it to the tree. We will append it as a new child of the body element
  document.body.appendChild(marquee);
  
  // After calling appendChild, the marquee will be visible since it will be a part of the tree
  // visible in the web page yet. We have the tree that represents the page
  //   html
  //   |
  //    - body
  //      |
  //       - Enter your name
  //       - input id="name"
  //       - button id="save"
  //         |
  //          - Guardar 
  //       - marquee
  //         |
  //         - Hello, Alfonso!

});

              
            
!
999px

Console