function addClass(el,cls){for(var c=el.className.split(" "),i=c.length-1;i>=0;i--)if(c[i]==cls)return;if(el.className=="")el.className=cls;else el.className+=" "+cls}function hasClass(el,cls){for(var c=el.className.split(" "),i=c.length-1;i>=0;i--)if(c[i]==cls)return tru...