I have a React component and I want to toggle a css class when clicked.

So I have this:

```
export class myComponent extends React.Component {
  constructor() {
    super();
    this.state = { clicked: false };
    this.handleClick = this.handleClick.bind(this);
  }

  render() {
    return (
      <div>
        <div onClick={this.clicked}><span ref="btn" className="glyphicon">&nbsp;</span></div>
      </div>
    );
  }

  handleClick() {
    this.refs.btn.classList.toggle('active');
  }

  componentDidMount() {
    this.refs.btn.addEventListener('click', this.handleClick);
    this.setState({
      clicked: this.state.clicked = true,
    });
  }

  componentWillUnmount() {
    this.refs.btn.removeEventListener('click', this.handleClick);
    this.setState({
      clicked: this.state.clicked = false,
    });
  }
}

```

This problem is that ESLint keeps telling me "this.refs" is depreciated.

What do I do instead? How can I fix it so it's not using depreciated code?