Handle browser's back button, dynamically load content, transition to replace content

gistfile1.js

$(window).bind("popstate", function() {
    $("body").css("cursor", "progress");
            
    $(".main").after("<section class='left'></section>");
    
    $(".left").load(location.pathname + " .main>*", function() {
        if ($(".left h1").text().length > 0)
            document.title = "Matt McCormick - " + $(".left h1").text();
        else
            document.title = "Matt McCormick";
        
        $("body").css("cursor", "auto");
        
        $(".main").animate({ left: widthB + "px"}, function() {
            $(".main").remove();
        });
        
        $(".left").show();
        $(".left").animate({ left: widthA + "px"}, function(){
            $(".left").addClass("main");
            $(".left").removeClass("left");
        });
    
        render();
        
        $("html, body").animate({ scrollTop:0 }, 0);
    });
});