function togglePanel(hintKey) {
	
	if(hints[hintKey]==1) { // if hint on, turn off
		document.getElementById('panel_'+hintKey).style.display = 'none';
		hints[hintKey]=0;
	} else if(hints[hintKey]==0) { // if hint off, turn on
		document.getElementById('panel_'+hintKey).style.display = 'block';
		hints[hintKey]=1;
	}
}