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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <h2>React - toggle class (ES6)</h2>
<a class ="link" href="https://codepen.io/_danko/pen/EypdyW" target="_blank">Check out ES5 version here</a>
<div id="app"></div>
              body {
  text-align: center;
  font-family: 'Roboto', sans-serif;
h2 {
  margin: 50px 0 10px;
.link {
  display: inline-block;
  margin-bottom: 50px;
.button {
  display: inline-block;
	font-size: 18px;
	color: #2f70e1;
	padding: 10px 30px; 
  margin-right: 10px;
  margin-bottom: 30px;
	box-shadow:	0px 1px 3px 0px rgba(0, 0, 0, .3);
  cursor: pointer;
  -webkit-user-select: none; /* Chrome/Safari */        
  -moz-user-select: none; /* Firefox */
  -ms-user-select: none; /* IE10+ */
.button-small {
  padding: 5px 10px;  
  font-size: 12px;
.toggled {
	background-color: #2f70e1;
	color: #fff;
button {
  margin-top: 80px;
              // just for a fun, button have parent and child components
// you can keep it simple and use just one component for button, but if you are learning React
// it's better for you to see how parent-child communication works on this simple example.
// btw, you can find button built from just one component (es5) here https://codepen.io/_danko/pen/yJqRWr
// n.b. in real life project do not use 'div' for a button - think about accessibility

class ButtonParent extends React.Component {
  constructor(props) {    
    this.state = {
      condition: false
    this.handleClick = this.handleClick.bind(this)
  handleClick() {
      condition: !this.state.condition
  render() {
    return (
        className={ this.state.condition ? "button toggled" : "button" }
        toggleClassName={ this.handleClick }
        Click me if you dare!

class ButtonChild extends React.Component {
  render() {
    return (
        className={ this.props.className }
        onClick={ this.props.toggleClassName }
        { this.props.children }

ReactDOM.render(<ButtonParent />, document.getElementById('app'))

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