Javascript : do a barrel roll en Konami Code

doabarrelroll = function()
{
    if (typeof(barrelrolls)=='undefined')
        barrelrolls = 0;
    barrelrolls++;
    var head = document.getElementsByTagName('head')[0];
    var style = document.createElement('style');
    var declarations = document.createTextNode('body { transform:rotate('+degBarrelRoll*barrelrolls+'deg); -ms-transform:rotate('+degBarrelRoll*barrelrolls+'deg); -moz-transform:rotate('+degBarrelRoll*barrelrolls+'deg); -webkit-transform:rotate('+degBarrelRoll*barrelrolls+'deg); -o-transform:rotate('+degBarrelRoll*barrelrolls+'deg); transition: '+secBarrellRoll+'s; -moz-transition: '+secBarrellRoll+'s; -webkit-transition: '+secBarrellRoll+'s; -o-transition: '+secBarrellRoll+'s; }');
    style.type = 'text/css';
    if (style.styleSheet)
        style.styleSheet.cssText = declarations.nodeValue;
    else
        style.appendChild(declarations);
    head.appendChild(style);
}
var kKeys = '';
$(document).keydown(function(e)
{
    kKeys = (kKeys+e.keyCode+',').slice(-30);
    if (kKeys.indexOf('38,38,40,40,37,39,37,39,66,65')>-1)
    {
        doabarrelroll();
        kKeys = '';
    }
});