responsive images
if (window.devicePixelRatio > 1) {
var images = $('img');
// console.log(images);
images.each(function(i) {
var originalImage = $(this).attr('src');
var retinaImage = originalImage.replace(".", "@2x.");
// var retinaImage = originalImage + "&density=2");
$(this).attr('src', retinaImage);
});
}