zdoc/assets/sass/components/_switch.scss

/* The switch - the box around the slider */
.switch {
  position: absolute;
  right: -2rem;
  top: 1.75rem;
  display: inline-block;
  width: 30px;
  height: 16px;
  z-index: z('gtt');
}

/* Hide default HTML checkbox */
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

/* The slider */
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: transparent;
  -webkit-transition: .2s;
  transition: .2s;

  &:before {
    position: absolute;
    content: "";
    height: 12px;
    width: 13px;
    left: 2px;
    bottom: 2px;
    -webkit-transition: .2s;
    transition: .2s;
  }

  &__icon {
    padding: 0.5rem;
  }
}

// input:checked + .slider {
//   @include themify($themes) {
//     background-color: transparent;
//   }
// }

// input:focus + .slider {
//   @include themify($themes) {
//     background-color: transparent;
//   }
// }

input:checked + .slider:before {
  -webkit-transform: translateX(13px);
  -ms-transform: translateX(13px);
  transform: translateX(13px);
}