css transition width code example
Example 1: css transition all
-webkit-transition: all .3s ease-in-out;
-moz-transition: all .3s ease-in-out;
-o-transition: all .3s ease-in-out;
-ms-transition: all .3s ease-in-out;
transition: all .3s ease-in-out;
Example 2: css opacity transition
div {
transition: opacity seconds;
}