/* raf_transitions.css */

/* Exercise 01 */
.hover-img {
  position: relative;
  width: 500px; height: 402px;
}
.hover-img > img {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%; 
}
.hover-img > .img2 {
  opacity: 0;
}
.hover-img:hover > .img2 {
  opacity: 1;
  transition: opacity 750ms ease-in-out;
}