JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://facebook.github.io/react/js/jsfiddle-integration.js"></script>

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

CSS

.green {
    background-color: lightgreen;
}

.blue {
    background-color: lightblue;
}

JavaScript

var Hello = React.createClass({
    getInitialState: function(){
        return {
            color: 'blue'
        };
    },
    handleClick: function(){
        if (this.state.color === 'blue'){
            this.setState({className = " green"});
        } else {
            this.setState({color: 'blue'});
        }
    },
    render: function() {
        return <button className={this.state.className} onClick={this.handleClick}>My background is: {this.state.color}, Click me to change</button>;
    }
});
 
React.render(<Hello name="World" />, document.getElementById('container'));