JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://fb.me/react-with-addons-0.12.0.js"></script>
<script src="http://fb.me/JSXTransformer-0.12.0.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.14.6/react.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.14.6/react-dom.js">
    </script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.13.1/react-with-addons.js"></script>

<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

CSS

.sample-enter {
     -webkit-transition: 1s ease-in;
}
.sample-enter.sample-enter-active {
    font-size: 80px;
}
.sample-leave {
    -webkit-transition: .5s ease-out;
}
.sample-leave.sample-leave-active {
    font-size: 10px;
}

React

var CSSTransitionGroup = React.addons.CSSTransitionGroup;

var Hello = React.createClass({
  getInitialState: function() {
    return {
      value: '(´・ω・｀)'
    };
  },
  onClick: function() {
    var value = this.state.value === '(´・ω・｀)' ? '(｀･ω･´)ゞ' : '(´・ω・｀)';
    this.setState({ value: value });
  },
  render: function() {
    var value = <span className="sample" key={this.state.value}>{this.state.value}</span>; 
    return (
      <div>
        <div>Animation!!<button onClick={this.onClick}>click!!</button></div>
        <CSSTransitionGroup transitionName="sample">
          {value}
        </CSSTransitionGroup>
      </div>
    );
  }
});

React.render(<Hello />, document.body);