switching/css/menu.css

* {
  box-sizing: border-box;
}


/* custom scrollbar */
::-webkit-scrollbar {
  width: .95em;
}
/* dummy content */
.content {
  float: left;
  margin: .75em 0 0 0;
  transition: margin .3s ease-in-out;
}
.content > p {
  margin: .25em 0 .75em 0;
}

/* Advanced Checkbox Hack */
body {
  -webkit-animation: bugfix infinite 1s;
}

@-webkit-keyframes bugfix {
  from {
    padding: 0;
  }
  to {
    padding: 0;
  }
}
input[type=checkbox] {
  position: absolute;
  top: -9999px;
  left: -9999px;
}

label {
  position: fixed;
  left: 0;
  display: none;
  width: 2em;
  height: .5em;
  padding: 20px;
  font-size: 1.1em;
  color: #fff;
  transition: color .3s ease-in-out;
  cursor: pointer;
  user-select: none;
  margin: 0;
#  background-color:blue;
}

/* big screens */
nav[role="off-canvas"] {
  position: relative;
  width: 50em;
  margin: 0 auto;
  transition-duration: .3s, .5s;
  transition-timing-function: ease-in-out;
  transition-property: left, opacity, box-shadow;
}
nav[role="off-canvas"] a {
  color: #fff;
  text-decoration: none;
  transition: color .3s ease-in-out;
  display: table-cell;
  vertical-align: middle;
}
nav[role="off-canvas"] ul {
  padding: 0;
  margin: 0 auto;
  width: 100%;
}
nav[role="off-canvas"] ul > li {
  float: left;
  padding: .55em .55em;
  width: 8em;
  margin: .5em;
  opacity: .8;
  text-transform: uppercase;
  display: table;
  cursor: pointer;
  text-align: center;
  transition-duration: .3s;
  transition-timing-function: ease-in-out;
  transition-property: box-shadow, color, opacity, padding-left;
  cursor: pointer;
}
nav[role="off-canvas"] ul > li:hover {
  color: #fff;
  opacity: 1;
  box-shadow: 0 0 0 0.5em rgba(255, 255, 255, 0.95);
}
nav[role="off-canvas"] ul > li
	.active
	{
  color: #fff;
  opacity: 1;
  box-shadow: 0 0 0 0.5em rgba(255, 255, 255, 0.95);
}

/* small screens */
@media screen and (max-width: 44em) {
  html,
  body {
    margin: 0;
    overflow-x: hidden;
  }

  .content {
    margin: 2.5em .5em 0 .5em;
  }

  nav[role="off-canvas"] {
    position: absolute;
    top: 3em;
    left: -20em;
    width: 20em;
    opacity: 0;
  }
  nav[role="off-canvas"] ul > li {
    height: 100%;
    width: 100%;
    text-align: left;
    margin: 0;
    background: black;
  }
  nav[role="off-canvas"] ul > li:hover {
    box-shadow: inset 0 0 0 0.15em rgba(255, 255, 255, 0.45);
  }

  label {
    display: block;
  }

  label:after {
    position: absolute;
    right: .25em;
    top: 0;
    content: "\2261";
    font-size: 1.8em;
  }

  label:hover,
  input:checked ~ label {
    color: #000;
  }

  input:checked ~ nav[role="off-canvas"] {
    opacity: 1;
    left: 0;
    box-shadow: -30em 0 0 30em rgba(0, 0, 0, 0.3);
  }
  input:checked ~ nav[role="off-canvas"] ul > li {
    padding: .55em .55em .55em 1.5em;
  }
  input:checked ~ nav[role="off-canvas"] ul > li:hover {
    padding-left: 3.5em;
  }
  input:checked ~ nav[role="off-canvas"] ul > li:after {
    position: absolute;
    right: .25em;
    content: "\203A";
    color: inherit;
  }

  input:checked ~ .content {
    margin-left: 20.5em;
    margin-right: -20.5em;
  }
}