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CSS CSS Basics Understanding Values and Units Em and Rem Units

Jessica Perry
Jessica Perry
1,687 Points

I want to make sure I'm understanding the math Correctly:

HTML 16px X Header 1.5em = 24pixels.right?so would be 1.5? Do i divide by the header? cause then i get 4.8 em.....@.@

style.css
/* Complete the challenge by writing CSS below */

html {
  font-size: 16px;
}

header {
  font-size: 1.5em;
}

.heading {
  font-size: 5rem;
}
h2{
font-size:3em
}
h3{
font-size:5em
}
index.html
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Developer Diane: Resume</title>
  <link rel="stylesheet" href="page.css">
  <link rel="stylesheet" href="style.css">
</head>
<body>
  <main>
    <header>
      <div id="header-box">
        <h1 class="heading">Developer Diane: Resume</h1>
        <address>
          <p>website: developerdiane.com</p>
          <p>email: diane@developerdiane.com</p>
        </address>
        <img src="developer-diane.jpg" alt="Developer Diane coding on her laptop.">
      </div>
    </header>          
    <section id="education">
      <h2>Education</h2>          
      <ul>
        <li>
          <h3><a href="https://teamtreehouse.com">Treehouse</a></h3>
          <p>Front End <em>Web Development</em> Techdegree</p>
          <p class="date special">Graduated January 2020</p>
        </li>
      </ul>
    </section>
    <section id="experience">
      <h2>Experience</h2>
      <ul>
        <li>
          <h3>Super Web Design Shop</h3>
          <p>Junior Developer</p>
          <p class="date special">February 2020-present</p>
        </li>
        <li>
          <h3>Pretty Good Websites, Inc.</h3>
          <p>Web Development Intern</p>
          <p class="date">July 2019-January 2020</p>
        </li>
      </ul>
    </section>
    <section>
      <h2>Skills</h2>
      <ul id="skills-list">
        <li class="top-skill">HTML</li>
        <li>CSS</li>
        <li class="top-skill" id="proud">JavaScript</li>
        <li>Git</li>
        <li>Bootstrap</li>
        <li class="top-skill">Mobile Web Development</li>
        <li>Accessibility</li>
      </ul>
    </section>
    <section>
      <h2>Awards and Achievements</h2>
      <ol>
        <li>Dev Ninja Award, November 2020</li>
        <li>Developer of the Month, October 2019</li>
        <li>Achieved rating of 6 kyu on <a href="https://www.codewars.com/">Codewars</a></li>
        <li>Certified Accessibility Specialist</li>
      </ol>
    </section>
    <footer>Ā©2020 Developer Diane.</footer>
  </main>
</body>
</html>

1 Answer

Hi! The header's font-size will be 24px. You don't have to divide anything. The difference between 'em' and 'rem' is that rem is relative to the main parent (in this case, the html element), and em takes into account every parent. For example, let's say the .heading class uses the em unit rather than the rem unit. The .heading's parent is the header element, and the header's parent ,in this case, is the html element, so the operations for .heading would be 16 x 1.5 x 5