text: console.log('app js is running');
  
  let visibility = false;
  
  let visibleText = () => {
    visibility = !visibility;
    renderContent();
  }
  
  let app = document.getElementById('app');
  
  let renderContent = () => {
    let visibleTemplate = (
      <div>
        <h1 className="mb-3">Visibility Toggle</h1>
        <button onClick={visibleText} className={visibility ? 'btn btn-primary': 'btn btn-secondary'}>
          {visibility ? 'Hide Details': 'Show Details'}
        </button>
        {visibility ? <p className="lead mt-3">Hi i am logical if</p>: <p className="lead mt-3">No content</p>}
        {
          visibility && (
            <div>
              <p className="lead">Hi i am logical and</p>
            </div>
          )
        }
      </div>
    );
    ReactDOM.render(visibleTemplate, app);
  }
  
  renderContent();