document.addEventListener('DOMContentLoaded', function() {
    var calendarEl = document.getElementById('googleView');

    var calendar = new FullCalendar.Calendar(calendarEl, {

      headerToolbar: {
        left: 'prev,next today',
        center: 'title',
        right: 'dayGridMonth,listYear'
      },

      displayEventTime: false, // don't show the time column in list view

      // THIS KEY WON'T WORK IN PRODUCTION!!!
      // To make your own Google API key, follow the directions here:
      // http://fullcalendar.io/docs/google_calendar/
      googleCalendarApiKey: 'AIzaSyDcnW6WejpTOCffshGDDb4neIrXVUA1EAE',

      // US Holidays
      events: 'en.usa#holiday@group.v.calendar.google.com',

      eventClick: function(arg) {
        // opens events in a popup window
        window.open(arg.event.url, 'google-calendar-event', 'width=700,height=600');

        arg.jsEvent.preventDefault() // don't navigate in main tab
      },

    });

    calendar.render();
  });