input[type="checkbox"] + label {
  position: absolute;
  width: 60px;
  height: 60px;
  border: 10px solid #555;
  border-radius: 100%;
  top: 50%;
  left: 10%;
  -webkit-transform: translate(-50%, -50%);
          transform: translate(-50%, -50%);
  -webkit-transition: all ease-out 200ms;
  transition: all ease-out 200ms;
  text-indent: 90px;
  font: normal normal 30px/60px "Helvetica";
  white-space: nowrap;
  color: #555;
  -webkit-user-select: none;
     -moz-user-select: none;
      -ms-user-select: none;
          user-select: none;
}
input[type="checkbox"] + label:after {
  content: "";
  position: absolute;
  width: 0px;
  height: 25px;
  border-bottom: 10px solid #22b573;
  border-left: 10px solid #22b573;
  top: 25%;
  left: 50%;
  -webkit-transform-origin: bottom left;
          transform-origin: bottom left;
  -webkit-transform: rotate(-45deg);
          transform: rotate(-45deg);
  opacity: 0;
  -webkit-transition: all ease-out 200ms;
  transition: all ease-out 200ms;
}

input[type="checkbox"]:checked + label {
  border: 10px solid #22b573;
}
input[type="checkbox"]:checked + label:after {
  opacity: 1;
  width: 70px;
}

#chk {
  display: none;
}