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<label class="md_switch">
  <input type="checkbox" />
  <span class="md_switch__toggle"></span>
  Toggle switch
</label>

<br>

<label class="md_switch">
  <input checked type="checkbox" />
  <span class="md_switch__toggle"></span>
  Pre-activated
</label>

<br>

<label class="md_switch">
  <input disabled type="checkbox" />
  <span class="md_switch__toggle"></span>
  Disabled
</label>

<br>

<label class="md_switch">
  <input checked disabled type="checkbox" />
  <span class="md_switch__toggle"></span>
  Activated and disabled
</label>

<br>

<label class="md_switch">
  <input type="checkbox" />
  <span class="md_switch__toggle"></span>
  Really really really long label <br>content to hopefully span several lines <br>to show that the checkbox will stay central.
</label>

@import url(http://fonts.googleapis.com/css?family=Open+Sans);

body {
  background: #F5F5F5;
}

.md_switch {
  display: inline-flex;
  font-family: "Open Sans";
  align-items: center;
  margin: 5px 0;
}

.md_switch .md_switch__toggle {
  position: relative;
  cursor: pointer;
}

.md_switch [type=checkbox] {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

/* default states */

.md_switch .md_switch__toggle::before,
.md_switch .md_switch__toggle::after {
  content: '';
  display: block;
  margin: 0 3px;
  transition: all 100ms cubic-bezier(0.4, 0.0, 0.2, 1);
  background: #BDBDBD;
}

.md_switch .md_switch__toggle::before {
  height: 1.3em;
  width: 3em;
  border-radius: 0.65em;
  opacity: 0.6;
}

.md_switch .md_switch__toggle::after {
  position: absolute;
  top: 50%;
  transform: translate(0, -50%);
  height: 1.7em;
  width: 1.7em;
  border-radius: 50%;
  box-shadow: 0 0 8px rgba(0,0,0,0.2), 0 0 2px rgba(0,0,0,0.4);
}

/* special states */
.md_switch [type=checkbox]:focus+.md_switch__toggle {
  outline: #5d9dd5 solid 1px;
  box-shadow: 0 0 8px #5e9ed6;
}

.md_switch [type=checkbox]:disabled+.md_switch__toggle {
  cursor: not-allowed;
  filter: grayscale(100%);
  opacity: 0.6;
}

.md_switch [type=checkbox]:disabled+.md_switch__toggle::after {
  box-shadow: none;
}

/* checked states */

.md_switch [type=checkbox]:checked+.md_switch__toggle::before,
.md_switch [type=checkbox]:checked+.md_switch__toggle::after{
  background: #00897B;
}

.md_switch [type=checkbox]:checked+.md_switch__toggle::after {
  transform: translate(calc(3em - 100%), -50%);
}