HTML

<input type="checkbox" id="checkbox_design">
<label for="checkbox_design">
  <span>체크박스 디자인</span>
</label>

CSS

input#checkbox_design{
  display: none;
}

input#checkbox_design + label{
  display: inline-block;
  position: relative;
  cursor: pointer;
  width: 20px;
  height: 20px;
  background: url(../img/unchecked.png);
}

input#checkbox_design:checked + label{
  background-image: url(../img/checked.png);
}

input#checkbox_design + label span{
  position: absolute;
  top: 0;
  left: 25px;
  font-size: 15px;
  width: 111px;
}