img {
  border: solid 10px white;
  border-bottom-width: 50px;
  margin: 10px;
  box-shadow: #ccc 2px 2px 4px;
}

li {
  list-style: none;
}
img {
  border: solid 10px white;
  border-bottom-width: 50px;
  margin: 10px;
  box-shadow: #ccc 2px 2px 4px;
  transition: border-color 0.4s;
}

li {
  list-style: none;
}
Add CSS cross-fade effect to color change
Add CSS cross-fade effect to color change
