Pen Settings

HTML

CSS

CSS Base

Vendor Prefixing

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JavaScript

Babel includes JSX processing.

Add External Scripts/Pens

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Packages

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Behavior

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Editor Settings

Code Indentation

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HTML

              
                <h2>box-sizing: content-box;</h2>
<div class="class">
  Size set to 200x100 pixels with real size 240x140 pixels.
</div>
<i><b>Note</b>: If you open Developer Tools, you can see that the real size of the element is <b>240x140</b> pixels. That is beacause we set CSS box model to content-box and browser added padding size value and border size value to the width and height of the element (in this case 2x10 pixels of padding and 2x10 pixels of border).</i>
              
            
!

CSS

              
                body {
  font-family: Helvetica;
  padding: 1em 2em;
}
div {
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  font-size: 16px;
}
.class {
  box-sizing: content-box;
  width: 200px;
  height:100px;
  padding: 10px; /* this value IS extending size of the element */
  border: 10px solid black; /* this value IS extending size of the element */
  margin: 20px 0;
  line-height: 1.5
}

i {
  font-size: 18px;
  margin-top: 2em;
  display: block;
  font-style: normal;
  line-height: 1.5;
}
              
            
!

JS

              
                
              
            
!
999px

Console