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HTML

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Adding Classes

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About the <head>

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. If you need things in the <head> of the document, put that code here.

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Insecure Resource

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CSS

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CSS Base

About CSS Base

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <header>
  <svg class="horizontal" width="293px" height="56px" viewBox="0 0 293 56" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
    <title>Code Red Logo &amp; Name</title>
    <desc>Logo is a forwad slash in pointy brackets</desc>
    <g id="Welcome" stroke="none" stroke-width="1" fill="none" fill-rule="evenodd">
      <g id="Mobile-Portrait---Menu-Open">
        <g id="Logo-&amp;-Name" transform="translate(146.500000, 28.000000) rotate(-90.000000) translate(-146.500000, -28.000000) translate(119.500000, -117.500000)">
          <path d="M172.5,118.5 L172.5,172.5 L-91.5,172.5 C-106.411688,172.5 -118.5,160.411688 -118.5,145.5 C-118.5,130.588312 -106.411688,118.5 -91.5,118.5 L-91.5,118.5 L172.5,118.5 Z" id="Combined-Shape" stroke="#D0021B" fill="#FFFFFF" transform="translate(27.000000, 145.500000) rotate(90.000000) translate(-27.000000, -145.500000) "></path>
          <g id="angle" transform="translate(26.500000, 26.500000) rotate(90.000000) translate(-26.500000, -26.500000) translate(4.000000, 4.000000)">
            <circle id="Oval" fill="#D0021B" cx="22.5" cy="22.5" r="22.5"></circle>
            <text id="&lt;/&gt;" font-family="CourierNewPS-BoldMT, Courier New" font-size="15.5889145" font-weight="bold" letter-spacing="1.03926095" fill="#FFFFFF">
              <tspan x="6.88282042" y="26.6662818">&lt;/&gt;</tspan>
            </text>
          </g>
          <text id="code–red.uk" transform="translate(26.500000, 167.500000) rotate(90.000000) translate(-26.500000, -167.500000) " font-family="CourierNewPSMT, Courier New" font-size="35.1219512" font-weight="normal" letter-spacing="2.34146345">
            <tspan x="-91.5400766" y="174" fill="#000000">code–</tspan>
            <tspan x="25.5502437" y="174" font-family="HelveticaNeue-Bold, Helvetica Neue" font-weight="bold" fill="#D0021B">red.uk</tspan>
          </text>
        </g>
      </g>
    </g>
  </svg>
  <button id="menuButton" onclick="menuToggle()" name="menu">Menu☰</button>
  <nav class="hidden" id="menu">
    <ul>
      <li>Ethos</li>
      <li>Services</li>
      <li>Work</li>
      <li>Case Studies</li>
      <li>Blog</li>
      <li>Contact</li>
      <li><a href="#" onclick="menuToggle()">Close X</a></li>
    </ul>
  </nav>
</header>
!

CSS 

              
                html {
  margin: 0;
  padding: 0;
  font-szie: 16px;
}
body {
  margin: auto;
  width: 320px;
  background-color: #FAF9F9;
}

header {
  position: relative;
  top: 0px; left 0;
  height: 45px;
  width: 100%;
  background-color: #D0021B;
  padding: 5px;
  margin: 0 0 0 27px;
}

svg {
  position: absolute;
  top: 1px; left: -30px;
  z-index: 10;
  
}

header.open svg {
  transform-origin: 28px 28px;
  transform: rotate(0deg);
  transition-delay: 0s;
}

header svg {
  transform-origin: 28px 28px;
  transform: rotate(90deg);
  transition: transform 2s ease;
  transition-delay: 2s;
}

button {
  background-color: #D0021B;
  color: #FAF9F9;
  font-family: 'Courier New';
  font-size: 2em;
  Font-weight: 700;
  text-decoration: underline;
  border: none;
  margin: 5px 0 0 30px;
  cursor: pointer;
}

button.hidden {
  color: #D0021B;
}

nav {
  max-height: 500px;
  transition: max-height 2s ease;
  transition-delay: 2s;
  overflow: hidden;
  margin-top: -40px;
  margin-left: -32px;
}

nav ul {
  background-color: #D0021B;
  color: #FAF9F9;
  font-family: 'Courier New';
  Font-weight: 700;
  font-size: 2em;
  list-style: none;
  margin: 23px 0 0 -27px;
  padding: 35px 10px 10px 33px; 
  border-radius: 0 0 23px 0;
}

nav ul a {
  color: #FAF9F9;
}

nav ul a:hover {
  background-color: #FAf9f9;
  color: #D0021B;
}

nav.hidden {
  max-height: 0;
  transition-delay: 0s;
}

/* Fallback for reduced-motion, no transition or no JavaScript
@media (prefers-reduced-motion) {
  nav.hidden {
    max-height: 500px;
  }
  header svg {
    transform: rotate(-90deg);
  }
}

@supports not (transition) {
  nav.hidden {
    max-height: 500px;
  }
}

.no-js nav.hidden {
  max-height: 500px;
 }
.no-js header svg {
  transform: rotate(-90deg);
}
*/
!

JS 

              
                const menuButton = document.querySelector("#menuButton");
const nav = document.querySelector("#menu");
const header = document.querySelector("header");

function menuToggle() {
  menuButton.classList.toggle("hidden");
  nav.classList.toggle("hidden");
  header.classList.toggle("open");
}
!
999px

Console