text: function navigateTo(view) {
    var page = '/view/' + view.replace(/ /g, '-');
    history.replaceState({view: view},
                         '从太空看流星雨 - ' + view,
                         page);
  
    if (typeof mixpanel !== 'undefined') {
      mixpanel.track('meteors', {
        view: view
      });
    }
    if (typeof ga !== 'undefined') {
      ga('send', 'pageview', '/' + page);
    }
  }
  