function clearSelection() { 
	var sel; 
	if(document.selection && document.selection.empty){ 
		document.selection.empty(); 
	} else if(window.getSelection) { 
		sel=window.getSelection(); 
		if(sel && sel.removeAllRanges) 
			sel.removeAllRanges();
	}
}

var changePage = function(url, object) {
	boink(url + object.options[object.selectedIndex].value);
}

function switchShow(url, obj) {
	boink(url + '?show=' + obj.options[obj.selectedIndex].value);
}

function boink(url, event) {
    if(event && event.metaKey) {
        form = document.createElement("form");
        form.method = "GET";
        form.action = url;
        form.target = "_blank";
        document.body.appendChild(form);
        form.submit();
    } else {
        document.location.href = url;
    }
}

var toggleLevels = function(obj, level) {
	$('hard').style.display = 'none';
	$('medium').style.display = 'none';
	$('easy').style.display = 'none';
	$('hard_link').removeClassName('active');
	$('medium_link').removeClassName('active');
	$('easy_link').removeClassName('active');
	$(level).style.display = 'block';
	obj.addClassName('active');
}