var Client = {
  viewportWidth: function() {
    return self.innerWidth || (document.documentElement.clientWidth || document.body.clientWidth);
  },

  viewportHeight: function() {
    return self.innerHeight || (document.documentElement.clientHeight || document.body.clientHeight);
  },
  
  viewportSize: function() {
    return { width: this.viewportWidth(), height: this.viewportHeight() };
  }
};