div {
background: #dbdbdb;
-webkit-transition: .5s all;
-webkit-transition-delay: 5s;
-moz-transition: .5s all;
-moz-transition-delay: 5s;
-ms-transition: .5s all;
-ms-transition-delay: 5s;
-o-transition: .5s all;
-o-transition-delay: 5s;
transition: .5s all;
transition-delay: 5s;
}
div:hover {
background:#5AC900;
-webkit-transition-delay: 0s;
-moz-transition-delay: 0s;
-ms-transition-delay: 0s;
-o-transition-delay: 0s;
transition-delay: 0s;
}
This will add a transition delay, which will be applicable to almost every browser..