input[type="checkbox"] {
  -webkit-appearance: none;
  -moz-appearance: none;
  cursor: pointer;
  background: #fff;
  outline:none;
}
input[type=checkbox][disabled]{ 
  background: #fff; 
}
input[type="checkbox"]:before {
  border: 1px solid #cccccc;
  content: "\00a0";
  display: inline-block;
  font: 27px/1em 'Exo 2', sans-serif;
  width: 27px;
  height: 27px;
  vertical-align: top;
  background: #fff;
}
input[type="checkbox"]:checked:before {
  background: #fff;
  color: #4994cd;
  content: "\2713";
  text-align: center;
}
input[type="checkbox"]:checked:after {
  font-weight: bold;
   background: #fff;
}