body {
  margin: 0;
  display: flex;
  justify-content: center;align-items: center;
  height: 100vh;
  background: #000000b3;
  transition: all 5s ease;
}
img {
  transition: all .6s ease;
  width: 500px;
  object-fit: cover;
}
img:hover {
  cursor: pointer;
  width: 100vw;
  height: 100vh;
}