<input type="checkbox" id="switch" /><label for="switch">Toggle</label>

input[type=checkbox]{
  height: 0;
  width: 0;
  visibility: hidden;
}

label {
  cursor: pointer;
  text-indent: -9999px;
  width: 200px;
  height: 100px;
  background: grey;
  display: block;
  border-radius: 100px;
  position: relative;
}

label:after {
  content: '';
  position: absolute;
  top: 5px;
  left: 5px;
  width: 90px;
  height: 90px;
  background: #fff;
  border-radius: 90px;
  transition: 0.3s;
}

input:checked + label {
  background: #bada55;
}

input:checked + label:after {
  left: calc(100% - 5px);
  transform: translateX(-100%);
}

label:active:after {
  width: 130px;
}

// centering
body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}