Summary  
This chapter explains the CSS box-sizing property (content-box, border-box, and inherit) and how it controls whether padding and borders are included in an element’s specified width and height.  

General domain of usage  
Front-end web layout and styling

Watch this video to see how the box-sizing property affects element sizing in CSS. You will learn the visual differences between content-box and border-box, and how these settings impact layout and spacing. This will help you understand how to control the width and height of elements more predictably in your web designs. Use simple css examples. Do not provide full html document stucture. Focus on css mainly

The `box-sizing` property is used to control how the total size of an element is calculated, specifically concerning its `width` and `height`. There are three possible values for the `box-sizing` property. Let's break down what each of these values means:
```css
box-sizing: content-box | border-box | inherit;
```

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<!DOCTYPE html>
<html lang="en">
  <head>
    <style>
      /* Current focus */
      /* Default behavior */
      .content-box {
        box-sizing: content-box;
        background-color: #e1f5fe;
      }

      /* Recommended modern behavior */
      .border-box {
        box-sizing: border-box;
        background-color: #fff3e0;
      }

      /* Additional styles for better appearance (not the current focus) */
      .wrapper {
        display: flex;
        justify-content: center;
        gap: 24px;
        padding: 10px;
        background-color: #f4f4f8;
        box-sizing: border-box;
      }

      .card {
        width: 200px;
        height: 200px;
        padding: 20px;
        border: 4px solid #4a90e2;
        border-radius: 12px;
        font-family: 'Fira Sans', sans-serif;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        font-size: 15px;
        line-height: 1.5;
        transition: all 0.3s ease;
      }

      h3 {
  text-align: center;
  margin-top: 0;
  font-size: 20px;
  font-weight: 600;
  color: #333;
}
    </style>
  </head>
  <body>
    <div class="wrapper">
      <div class="card content-box">
        <h3>content-box</h3>
        <p>
          The padding and border are added on top of the width and height. So
          the total size becomes larger than 200px.
        </p>
      </div>

      <div class="card border-box">
        <h3>border-box</h3>
        <p>
          The padding and border are included in the 200px width and height. The
          box stays exactly 200px.
        </p>
      </div>
    </div>
  </body>
</html>


## inherit
The `inherit` value allows an element's `box-sizing` property to inherit its value from its parent element. This means that the `box-sizing` behavior of the current element is determined by the `box-sizing` property of its parent element.

What is the default value for the `box-sizing` property?

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Box Sizing and Width Control

Output

inherit