function openpopup( popupName ) {
	
	var popup = null;
	var width=530;
	var height=580;		
	var theURL='';
	var winName='';
	var topY=(screen.height-height)/2;
	var leftX=(screen.width-width)/2;		
	var features='innerWidth=' + width+',innerHeight='+height+',width=' + width+',height='+height+',top='+topY+',left='+leftX+',resizable=0,scrollbars=0,toolbar=no,status=no,location=no';
						
	if( popupName =='regulamin_konkursu' ) {
		theURL='popups/regulamin_konkursu.html';
		winName='regulamin_konkursu';
	} else if( popupName =='regulamin_serwisu' ) {
		theURL='popups/regulamin_serwisu.html';
		winName='regulamin_serwisu';
	}  

	if( !winName || !theURL ) {
		alert( 'Not defined: ' + popupName );
		return;
	}	
	
	popup = window.open(theURL,winName,features);	

	if ( popup && !popup.closed ) {
		popup.focus();
	}
}