input[type="checkbox"]{
  display: none;
}
input[type="checkbox"] + label{
  display: inline-block;
  position: relative;
  padding-left:30px;
}
input[type="checkbox"] + label::before{
  display:block;
  content:'';
  font-size: 20px;
  width: 20px;
  height: 20px;
  line-height:20px;
  text-align: center;
  position: absolute;
  left: 0;
  top:0;
  border:1px solid #ddd;
  color:blue;
}

input[type="checkbox"]:checked + label::before{
  content:'✔';
}