/**
 * Elements that make up the popup.
 */
var container = document.getElementById('popup');
var content = document.getElementById('popup-content');
var closer = document.getElementById('popup-closer');

/**
 * Create an overlay to anchor the popup to the map.
 */
var overlay = new ol.Overlay(/** @type {olx.OverlayOptions} */ ({
  element: container,
  autoPan: true,
  autoPanAnimation: {
    duration: 250
  }
}));

/**
 * Add a click handler to hide the popup.
 * @return {boolean} Don't follow the href.
 */
closer.onclick = function() {
  overlay.setPosition(undefined);
  closer.blur();
  return false;
};


