<h1><span style="font-size:2.75em;">100% CSS</span><br>Hamburger Animation</h1>

<input id="toggle" type="checkbox"></input>

<label for="toggle" class="hamburger">
  <div class="top-bun"></div>
  <div class="meat"></div>
  <div class="bottom-bun"></div>
</label>

<div class="nav">
  <div class="nav-wrapper">
    <nav>
      <a href="#">HOME</a><br>
      <a href="#">ABOUT</a><br>
      <a href="#">WORK</a><br>
      <a href="#">SERVICES</a>
    </nav>
  </div>
</div>
body {
  background: #336193;
  color: #6ecddd;
  font-family: 'Bebas';
  text-align: center;
  max-width: 100%;
  overflow-x: hidden;
  padding: 0;
  margin: 0;
}
h1 {
  text-align: center;
  letter-spacing: 1px;
  word-spacing: 0.15em;
  font-size: 3em;
  line-height: 1.2;
  transform: translateY(52%);
}


#toggle {
  display: none;
}

/**
  Hamburger
**/
.hamburger {
  position: absolute;
  top: 5em;
  right: 5%;
  margin-left: -2em;
  margin-top: -45px;
  width: 2em;
  height: 45px;
  z-index: 5;
}

.hamburger div {
  position: relative;
  width: 3em;
  height: 7px;
  border-radius: 3px;
  background-color: #f8982b;
  margin-top: 8px;
  transition: all 0.3s ease-in-out;
}

/**
Nav Styles
**/
.nav {
  position: fixed;
  width: 100%;
  height: 100%;
  background-color: #090E6B;
  top: -100%; left: 0; right: 0; bottom: 0;
  overflow: hidden;
  transition: all 0.3s ease-in-out;
  transform: scale(0);
}
.nav-wrapper {
  position: relative;
  overflow: hidden;
  overflow-y: auto;
  height: 100%;
}
nav {
  text-align: left;
  margin-left: 25%;
}
nav a {
  position: relative;
  text-decoration: none;
  color: #6ecddd;
  font-size: 2em;
  display: inline-block;
  margin-top: 1.25em;
  transition: color 0.2s ease-in-out;
  letter-spacing: 1px;
}
nav a:before {
  content: '';
  height: 0;
  position: absolute;
  width: 0.25em;
  background-color: white;
  left: -0.5em;
  transition: all 0.2s ease-in-out;
}
nav a:hover {
  color: white;
}
nav a:hover:before {
  height: 100%;
}

/**
Animations
**/
#toggle:checked + .hamburger .top-bun {
  transform: rotate(-45deg);
  margin-top: 25px;
}
#toggle:checked + .hamburger .bottom-bun {
  opacity: 0;
  transform: rotate(45deg);
}
#toggle:checked + .hamburger .meat {
  transform: rotate(45deg);
  margin-top: -7px;
}

#toggle:checked + .hamburger + .nav {
  top: 0;
  transform: scale(1);
}

External CSS

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External JavaScript

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