scrollTo() without plugin

index.html

<div id="top">Hello, I'm the top-gun!</div>
<div id="bottom">Hello, I'm the bottom end :(</div>

script.js

var documentBody = (($.browser.chrome)||($.browser.safari)) ? document.body : document.documentElement;

$('#top').click(function() {
    $(documentBody).animate({scrollTop: $('#bottom').offset().top}, 2000,'easeInOutCubic');
});

$('#bottom').click(function() {
    $(documentBody).animate({scrollTop: $('#top').offset().top}, 2000,'easeInOutCubic');
});

style.css

#top {
    position: absolute;
    top: 0;
}

#bottom {
    position: absolute;
    top: 1200px;
}