Edit on
<input type="checkbox" id="togglebox" />

<nav id="offcanvas-menu">
  Menu contents to be added
</nav>

<div id="contentarea">
  <label for="togglebox" id="navtoggler">Menu</label>
  Some body content here some body content here
</div>
div#contentarea {
  position: relative;
  width: 100%;
  -moz-transform: translate3d(0, 0, 0);
  -webkit-transform: translate3d(0, 0, 0);
  transform: translate3d(0, 0, 0);
  -moz-transition: -moz-transform 0.5s;
  /* transition settings */
  
  -webkit-transition: -webkit-transform 0.5s;
  transition: transform 0.5s;
}

input[type="checkbox"]#togglebox {
  /* checkbox used to toggle menu state */
  position: absolute;
  left: 0;
  top: 0;
  visibility: hidden;
}

label#navtoggler {
  /* Main label icon to toggle menu state */
  z-index: 9;
  display: block;
  position: relative;
  font-size: 8px;
  /* change font size to change label dimensions. Leave width/height below alone */
  width: 4em;
  height: 2.5em;
  top: 0;
  left: 0;
  text-indent: -1000px;
  border: 0.6em solid black;
  /* border color */
  border-width: 0.6em 0;
  cursor: pointer;
}

label#navtoggler::before {
  /* inner strip inside label */
  content: "";
  display: block;
  position: absolute;
  width: 100%;
  height: 0.6em;
  top: 50%;
  margin-top: -0.3em;
  left: 0;
  background: black;
  /* stripes background color. Change to match border color of parent label above */
}

nav#offcanvas-menu {
  /* Full screen nav menu */
  width: 250px;
  height: 100%;
  top: 0;
  left: 0;
  z-index: 100;
  visibility: hidden; /* this is for browsers that don't support CSS3 translate3d */
  -moz-transform: translate3d(-250px, 0, 0);
  -webkit-transform: translate3d(-250px, 0, 0);
  transform: translate3d(-250px, 0, 0);
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  background: #C1F2BC;
  display: block;
  position: fixed;
  text-align: center;
  overflow: auto;
  -moz-transition: -moz-transform 0.5s, visibility 0s 0.5s;
  /* transition settings */
  -webkit-transition: -webkit-transform 0.5s, visibility 0s 0.5s;
  transition: transform 0.5s, visibility 0s 0.5s;
}

input[type="checkbox"]#togglebox:checked ~ div#contentarea {
  margin-left: 10px;
  -moz-transform: translate3d(250px, 0, 0);
  -webkit-transform: translate3d(250px, 0, 0);
  transform: translate3d(250px, 0, 0);
}

input[type="checkbox"]#togglebox:checked ~ nav#offcanvas-menu {
  /* nav state when corresponding checkbox is checked */
  -moz-transform: translate3d(0, 0, 0);
  -webkit-transform: translate3d(0, 0, 0);
  transform: translate3d(0, 0, 0);
  visibility: visible; /* this is for browsers that don't support CSS3 translate3d in showing the menu */
  -moz-transition-delay: 0s; /* No delay for applying "visibility:visible" property when menu is going from "closed" to "open" */
  -webkit-transition-delay: 0s;
  transition-delay: 0s;
}
Rerun