Burger Menu

//HTML
<div id="burger">
    <button class="hamburger hamburger--elastic ripple" type="button">
      <span class="hamburger-box">
        <span class="hamburger-inner"></span>
      </span>
    </button>
  </div>


//CSS
.hamburger {
  display: inline-block;
  overflow: visible;
  padding: 15px;
  transition-timing-function: linear;
  transition-duration: .15s;
  transition-property: opacity,filter;
  border: 0;
  float: right;
  background-color: transparent;
  outline: 0;
  outline-style: none;
  cursor: pointer;
}

.hamburger-box {
  position: relative;
  display: inline-block;
  width: 35px;
  height: 24px
}

.hamburger--elastic .hamburger-inner {
  top: 2px;
  transition-timing-function: ease;
  transition-duration: .5s
}

.hamburger-inner,.hamburger-inner:after,.hamburger-inner:before {
  position: absolute;
  width: 100%;
  height: 2px;
  background-color: #000;
  left: 0;
  transition: all .5s cubic-bezier(.165,.84,.44,1);
}

.hamburger-inner:after,.hamburger-inner:before {
  display: block;
  content: "";
  
}

.hamburger--elastic .hamburger-inner:before {
  top: 10px;
}

.hamburger--elastic .hamburger-inner:after {
  top: 20px;
  transition: all .5s ease
}

.hamburger-inner:after {
  bottom: -10px
}

.hamburger--elastic.is-active .hamburger-inner {
  transition-delay: 75ms;
  transform: translate3d(0, 10px, 0) rotate(135deg)
}

.hamburger--elastic.is-active .hamburger-inner:before {
  transition-delay: 0s;
  opacity: 0
}

.hamburger--elastic.is-active .hamburger-inner:after {
  transition-delay: 75ms;
  transform: translate3d(0, -20px, 0) rotate(-270deg)
}

//Javascript

var menu_nav = document.querySelector("#burger");
if (menu_nav != null) {
  menu_nav.addEventListener('click', function () {
    global_menu.classList.add('active');
    mybody.classList.add('menu_active');
  });
  close_menu.addEventListener('click', function () {
    global_menu.classList.remove('active');
    mybody.classList.remove('menu_active');
  });
}

function checkKey(e) {
  e = e || window.event;

  if (e.keyCode == "27") {
    $("#global_menu").removeClass("active");
    $("body").removeClass("menu_active");
    $("#burger button").removeClass('is-active');
    $("#header").removeClass("showing_menu");
  }
 }
 document.onkeydown = checkKey;