function makeactive(tab) 
{
	for (i=1;i<=3;i++)
	{
		document.getElementById("tab"+i).className = ""; 
		document.getElementById("content"+i).className = "tabhide";
		if(i == tab)
			document.getElementById("content"+i).className = "tabshow";
	}
	document.getElementById("tab"+tab).className = "active";
}