[type=radio] { 
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

/* IMAGE STYLES */
[type=radio] + img {
  cursor: pointer;
    width: 40px;
    height: 40px;
    margin: 10px;
}

/* CHECKED STYLES */
[type=radio]:checked + img {
  width: 50px;
  height: 50px;
}