function toggleCells(el){
	rCells=document.getElementsByTagName('div');
	for (i = 0; i < rCells.length; i++)
		if (rCells[i].className=='active')
			rCells[i].className='normal';
	el.className='active';
}
function change(ev){
if(ev.className=='normal'){
	ev.className='over';	
}
else if(ev.className=='over'){
	ev.className='normal';
}
}