* { transition-duration: .5s; }

html,
body { height: 100%;/*    overflow: hidden;*/
}

#drawer-toggle-label:before {
  content: "";
  display: block;
  position: absolute;
  height: 2px;
  width: 24px;
  background: #fff;
  left: 13px;
  top: 18px;
  box-shadow: 0 6px 0 #fff, 0 12px 0 #fff;
}

#drawer-toggle-label {
  display: block;
  position: fixed;
  top: 0;
  left: 0;
  height: 50px;
  width: 50px;
  z-index: 1;
  background: transparent;
}

#drawer-toggle { display: none; }

header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  text-align: center;
  height: 50px;
  background: #8d8d8d;
}

header h3 {
  margin: 0;
  line-height: 50px;
  color: #fff;
}

#drawer {
  position: fixed;
  top: 0;
  padding-top: 50px;
  height: 100%;
  width: 250px;
  background: #2f2f2f;
  overflow-x: hidden;
  overflow-y: auto;
  left: -250px;
 background:
}

#drawer ul {
  list-style: none;
  padding: 0;
}

#drawer li a {
  display: block;
  color: #fff;
  text-decoration: none;
  text-align: center;
}

#drawer li {
  margin: 0;
  width: 100%;
  padding: 10px 0
}

#drawer { padding-top: 10px; }

.content-wrapper {
  box-sizing: border-box;
  margin: 50px 0 0 0;
  width: 100%;
  height: calc(100%-50px);
  overflow-x: hidden;
  overflow-y: auto;
  overflow-scrolling: touch;
  padding: 20px;
}

#drawer-toggle:checked ~ #drawer-toggle-label,
#drawer-toggle:checked ~ header { left: calc(100% - 50px); }

#drawer-toggle:checked ~ #drawer {
  width: calc(100% - 50px);
  left: 0;
}

#drawer-toggle:checked ~ section.content-wrapper { margin-left: 250px; }
 @media screen and (min-width: 380px) {

.content-wrapper { background: tomato; }

#drawer-toggle:checked ~ #drawer-toggle-label,
#drawer-toggle:checked ~ header { left: 300px; }

#drawer-toggle:checked ~ #drawer {
  width: 300px;
  left: 0;
}
}