// IE8 polyfill
HTMLDocument.prototype.getElementsByClassName =
Element.prototype.getElementsByClassName =
function getElementsByClassName (className) {
for (var res = [], els = this.getElementsByTagName('*'), n = els.length; n--;) {
if (els[n].className.indexOf(className) > -1) {
res.push(els[n]);
}
}
return res;
}
// prevent selection because it's annoying when dragging
document.onselectstart = function(){ return false; };
document.body.setAttribute('unselectable', 'on', 0);