function get_active(id){	
	document.getElementById('left_'+id).className = 'leftactive';
	document.getElementById('center_'+id).className = 'topactive';
	document.getElementById('right_'+id).className = 'rightactive';
}
function get_unactive(id){		
	document.getElementById('left_'+id).className = 'bgnone';	
	document.getElementById('center_'+id).className = 'bgnone';
	document.getElementById('right_'+id).className = 'bgnone';		
}