Check if element is within viewport

check.js

Popover.prototype.isOverlappingViewport = function($el) {
    return this.getElementBoundaries($el).top < 0? true : false ||
           this.getElementBoundaries($el).bottom > $('body').height()? true : false ||
           this.getElementBoundaries($el).left < 0? true : false ||
           this.getElementBoundaries($el).right > $('body').width()? true : false;
  };