whmcsDNSManager/modules/addons/DNSManager2/templates/admin/assets/css/icheck/all.css

.checkbox-styled {
  position: relative;
  display: inline-block;
  height: 18px;
  width: 18px;
  margin: 0 5px 4px 0;
  background-color: #fff;
  border: 1px solid #DADADA;
  border-radius: 2px;
  -webkit-transition: 0.15s ease-in-out;
  transition: 0.15s ease-in-out;
  cursor: pointer;
  vertical-align: middle;
}

.checkbox-styled:before {
  position: absolute;
  top: 50%;
  left: 50%;
  display: block;
  content: "\f00c";
  height: 0;
  width: 0;
  opacity: 0;
  color: #25c268;
  font-size: 0;
  font-family: 'FontAwesome';
  line-height: 16px;
  text-align: center;
  line-height: 1px;
  -webkit-transition: 0.15s ease-in-out;
  transition: 0.15s ease-in-out;
}
.checkbox-styled.checked:before{
  top: 0;
  left: 0;
  height: 16px;
  width: 16px;
  opacity: 1;
  font-size: 14px;
  line-height: 16px;
}

.checkbox-styled:not(.disabled):hover {
    border: 1px solid #25c268;
}

.checkbox-styled.disabled {
    border: 1px solid #EEEEEE;
}

.checkbox-styled.disabled:before {
    color: #BED1C6;
}