cd.tsx

  getExplanationSection() {
    const explanation = this.props.explanation;
    if (explanation !== undefined) {
      return (
        <div onClick={() => this.setState({ expanded: !this.state.expanded })}>
          <section className={'nokkeltall-explanation'}>
            {explanation}
          </section>
        </div>
      );
    }
  }

  render() {
    const { value, title, subtitle } = this.props;
    const expanded = this.state.expanded;
    return (
      <article className='nokkeltall'>
        <section className='nokkeltall-content'>
          <div className='nokkeltall-number'>{nokkeltallValueFormat(value)}</div>
          <h3 className='nokkeltall-subtitle'>{subtitle}</h3>
          <h2 className='nokkeltall-title'>{title}</h2>
        </section>
        {this.getExplanationSection()}
        <button className='nokkeltall-expand-icon'>
          {expanded
            ? <i className='icon-up-open-big'></i>
            : <i className='icon-down-open-big'></i>
          }
        </button>
      </article>);
  }