burger menu css

CSS
/* Link to Codepen in source for PoC */

<style>
.container {
  background: dodgerblue;
  padding: 20px;
  height: 70px;
}

#hamburger {
  width: 40px;
  height: 40px;
  display: block;
  position: relative;
  float: right;
  transform: rotate(0deg);
  transition: .5s ease-in-out;
  cursor: pointer;
}
#hamburger span {
  display: block;
  position: absolute;
  height: 4px;
  width: 100%;
  background: white;
  border-radius: 9px;
  opacity: 1;
  left: 0;
  transform: rotate(0deg);
  transition: .25s ease-in-out;
}
#hamburger span:nth-child(1) {
  top: 0px;
}
#hamburger span:nth-child(2) {
  top: 12px;
}
#hamburger span:nth-child(3) {
  top: 24px;
}
#hamburger.open span:nth-child(1) {
  top: 14px;
  transform: rotate(135deg);
}
#hamburger.open span:nth-child(2) {
  opacity: 0;
  left: -60px;
}
#hamburger.open span:nth-child(3) {
  top: 14px;
  transform: rotate(-135deg);
}

</style>
<body>
  <div class="container">
       <div id="hamburger">
          <span></span>
          <span></span>
          <span></span>
      </div> 
  </div>
</body>
<div class="container" onclick="myFunction(this)">
  <div 
class="bar1"></div>
  <div class="bar2"></div>
  <div 
class="bar3"></div>
</div> 
Source

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