What do you want to fade? The background
or color
attribute?
Currently you're changing the background color, but telling it to transition the color property. You can use all
to transition all properties.
.clicker {
-moz-transition: all .2s ease-in;
-o-transition: all .2s ease-in;
-webkit-transition: all .2s ease-in;
transition: all .2s ease-in;
background: #f5f5f5;
padding: 20px;
}
.clicker:hover {
background: #eee;
}
Otherwise just use transition: background .2s ease-in
.