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CSS CSS Layout Box Model Concepts Viewport Units

vh

Refers to: Viewport Units

style.css
.header {
  height 25%;
}
index.html
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Developer Diane's blog</title>
  <link rel="stylesheet" href="page.css">
  <link rel="stylesheet" href="style.css">
</head>
<body>
  <header>
    Developer Diane’s Blog
  </header>
  <article>
    <section class="intro">
      <h1>The verdict is in. CSS Layout is great!</h1>
      <p>I’ve been working with CSS for a while now, and I have to say, it’s pretty awesome. I love being able to separate content from presentation, and to keep all my styles in an external stylesheet.</p>
      <p>I’ve had a pretty good grasp on the basics for a while now, but I needed to learn more about how to control layout with my CSS. Understanding CSS layout meant first exploring the parts of the CSS box model.</p>
    </section>
    <section class="featured">
      <h2>The CSS Box Model</h2>
      <p>There are lots of great resources online to help you learn the CSS Box Model. I like the CSS Tricks article <a href="https://css-tricks.com/the-css-box-model/" target="_blank">The CSS Box Model</a> by Chris Coyier. To quote the author:</p>
      <blockquote>At the risk of over-repeating myself: <strong>every element in web design is a rectangular box.</strong></blockquote>
      <p>That’s right! Every HTML element is considered by the browser to be a rectangular box.</p>
      <p>The CSS Box Model consists of four properties: content, padding, border, and margin. I've included a graphic from Coyier’s article to illustrate this principle.</p>
      <p class="clear">It’s pretty easy to understand the Content portion of the box model. The content is whatever your HTML consists of. It could be a paragraph full of text, or a bulleted list, or an image.</p>
      <p>Beginning developers may have some trouble keeping the other parts of the box model straight, so let’s examine them one by one.</p>
    </section>
    <footer>©2020 Developer Diane.</footer>
</body>
</html>

1 Answer

Rick Gleitz
Rick Gleitz
47,877 Points

Hi Vincent,

Couple of minor problems here. First, header is an element, so no period in front of it. Second, the unit is not %, but vh.

Hope this helps!