content: import React from 'react';
  import classes from './Counter.scss';
  
  export const Counter = (props) => (
    <div>
      <h2 className={classes.counterContainer}>
        Counter:
        {' '}
        <span className={classes['counter--green']}>
          {props.counter}
        </span>
      </h2>
      <button className="btn btn-default" onClick={props.increment}>
        Increment
      </button>
      {' '}
      <button className="btn btn-default" onClick={props.doubleAsync}>
        Double (Async)
      </button>
    </div>
  );
  
  Counter.propTypes = {
    counter: React.PropTypes.number.isRequired,
    doubleAsync: React.PropTypes.func.isRequired,
    increment: React.PropTypes.func.isRequired
  };
  
  export default Counter;
  