function changeColor(ob)
	{
		//alert(ob.style.color);
	//	if(!ob.style || ob.style.color=="black" ) {ob.style.color="white"};
		//if(ob.style.color=="white" ) {ob.style.color="black"};
		
		
		if(ob.style.color=="gray")
		{
			ob.style.color="black";
		}
		else
		{
			ob.style.color="gray";
		}
	
	
	
	}