var defaultOffset;

function centerInPage() {
    var viewPortHeight = $(window).height();
    var elementHeight = 580;
    var verticalOffset = parseInt((viewPortHeight - elementHeight)/2);
    if (verticalOffset>defaultOffset) {
        $('#page').css('margin-top',verticalOffset + 'px');
    } else {
        $('#page').css('margin-top',defaultOffset + 'px');
    }
}

$(document).ready(function() {
    defaultOffset = parseInt($('#page').css('margin-top'));
    centerInPage();
    $(window).resize(function(){
        centerInPage();
    });
    //$('.scroll_pane').jScrollPane({animateTo:true, animateInterval:50, animateStep:5, showArrows:false});
});