/*Button*/
.button {
    position: absolute;
}
   .button img:nth-child(2){
  display: none;
  }
  .button:hover img:nth-child(1){
  display: none;
  }
  .button:hover img:nth-child(2) {
    display: block;
}

/*Navigtion*/
.nav {
  background: #acc8dd;
  padding: 40px;
  margin: 5px;     
  border-radius: 5px;
}