custom-checkbox-radio-buttons.css

.js .nc-button-wrapper {
  position: relative;
}

.js .nc-button-wrapper input[type=radio],
.js .nc-button-wrapper input[type=checkbox] {
  /* hide native checkbox and radio input if JavaScript is enabled */
  position: absolute;
  left: 0;
  top: 0;
  margin: 0;
  padding: 0;
  opacity: 0;
}

.nc-button-wrapper svg {
  /* svg icon is hidden by default */
  display: none;
}

.js .nc-button-wrapper svg {
  /* show custom svg icon if JavaScript is enabled */
  display: block;
  position: absolute;
  /* IE9 and IE10 support pointer-events on SVG elements while they don't support it on HTML elements */
  pointer-events: none;
  left: 0;
  top: 50%;
  -webkit-transform: translateY(-50%);
      -ms-transform: translateY(-50%);
          transform: translateY(-50%);
}

.js .nc-button-wrapper label {
  position: relative;
  padding-left: 20px;
}