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HTML

            
              <p id="out">Click on some stuff. I'll keep track of how many times you've clicked each element</p>

<h1 class="title-shadow-box">The Mozilla Manifesto</h1>
<section id="introduction">
  <h2>Introduction</h2>
  <p>The Internet is becoming an increasingly important part of our lives.</p>
  <p>The Mozilla project is a global community of people who believe that openness, innovation, and opportunity are key to the continued health of the Internet. We have worked together since 1998 to ensure that the Internet is developed in a way that benefits everyone. We are best known for creating the Mozilla Firefox web browser.</p>
  <p>The Mozilla project uses a community-based approach to create world-class open source software and to develop new types of collaborative activities. We create communities of people involved in making the Internet experience better for all of us. </p>
  <p>As a result of these efforts, we have distilled a set of principles that we believe are critical for the Internet to continue to benefit the public good as well as commercial aspects of life. We set out these principles below.</p>
  <p>The goals for the Manifesto are to:</p>
  <ol>
    <li>articulate a vision for the Internet that Mozilla participants want the Mozilla Foundation to pursue; </li>
    <li>speak to people whether or not they have a technical background;</li>
    <li>make Mozilla contributors proud of what we're doing and motivate us to continue; and</li>
    <li>provide a framework for other people to advance this vision of the Internet.</li>
  </ol>
  <p>These principles will not come to life on their own. People are needed to make the Internet open and participatory - people acting as individuals, working together in groups, and leading others. The Mozilla Foundation is committed to advancing the principles set out in the Mozilla Manifesto. We invite others to join us and make the Internet an ever better place for everyone.</p>
</section>
<section id="principles">
  <h2>Principles</h2>
  <ol>
    <li>The Internet is an integral part of modern life—a key component in education, communication, collaboration, business, entertainment and society as a whole. </li>
    <li>The Internet is a global public resource that must remain open and accessible.</li>
    <li>The Internet must enrich the lives of individual human beings.</li>
    <li>Individuals’ security and privacy on the Internet are fundamental and must not be treated as optional.</li>
    <li>Individuals must have the ability to shape the Internet and their own experiences on the Internet.</li>
    <li>The effectiveness of the Internet as a public resource depends upon interoperability (protocols, data formats, content), innovation and decentralized participation worldwide.</li>
    <li>Free and open source software promotes the development of the Internet as a public resource.</li>
    <li>Transparent community-based processes promote participation, accountability and trust.</li>
    <li>Commercial involvement in the development of the Internet brings many benefits; a balance between commercial profit and public benefit is critical.</li>
    <li>Magnifying the public benefit aspects of the Internet is an important goal, worthy of time, attention and commitment.</li>
  </ol>
  <hr>
  <p><a href="https://www.mozilla.org/en-US/about/manifesto/details/">read the whole thing</a></p>
</section>
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CSS

            
              #out {
  background-color: #ffc;
  color: black;
  border-radius: 0.5em;
  padding: 0.5em;
  position: fixed;
  top: 0;
  box-shadow: 3px 3px 8px rgba(0, 0, 0, 0.2);
}

h1 {
  margin-top: 3em;
}

body {
  font-family: sans-serif;
  max-width: 60em;
  margin-left: auto;
  margin-right: auto;
}

body * {
  border: 2px solid transparent;
  -moz-transition: border-color 1s ease;
  transition: border-color 1s ease;  
}

body *:hover {
  border: 2px solid red;
}
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JS

            
              // Demo showing how symbols can be used to attach properties
// to DOM objects. (Caveat: I'm not sure how this works with
// forms, since those have property getters.)

(function () {
  // Note: This Symbol is mostly only visible in the
  // enclosing function.
  var clickCount = Symbol("clickCount");

  document.body.addEventListener("click", event => {
    event.stopPropagation();
    var me = event.target;
    me.clickCount = (me.clickCount || 0) + 1;
    document.getElementById("out").innerHTML = `
      This ${me.tagName} element
      has been clicked ${me.clickCount == 1
                         ? "once"
                         : me.clickCount + " times"}.
    `;
  });
})();
!
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