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CSS CSS Basics Understanding Values and Units Pixels and Percentages

Abdul Khan
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.a{fill-rule:evenodd;}techdegree
Abdul Khan
Front End Web Development Techdegree Student 1,344 Points
Posted by Abdul Khan
.a{fill-rule:evenodd;}techdegree
Abdul Khan
Front End Web Development Techdegree Student 1,344 Points

reduce header width 80%

I don't know what I'm doing wrong I selected the header and trying to reduce the width and it is still not working?

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

.heading {
  font-size: 48px;
}
h2 {
    font-size: 32px;

}
.main-nav {
  Width: 80%;
}
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 class="main-nav">
      <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>

2 Answers

Taino Dominguez
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.a{fill-rule:evenodd;}techdegree seal-36
Taino Dominguez
Front End Web Development Techdegree Graduate 20,013 Points
Taino Dominguez
.a{fill-rule:evenodd;}techdegree seal-36
Taino Dominguez
Front End Web Development Techdegree Graduate 20,013 Points

Due to the wording of the question, "reduce the width of the header element" , you will want to target the header directly, not the class like so ->

header { width: 80%; }

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,252 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,252 Points

Just change the width property. should be in all lower case or CSS won't understand it as a width property.

width: 80%;