function hideLevelDev(_mlevelId) {
    var thisLevel = document.getElementById(_mlevelId);
    thisLevel.style.display = "none";
}

function initialHidingDev() {
	hideLevelDev("polI");
    hideLevelDev("polA");
    hideLevelDev("polB");
    hideLevelDev("polC");
	hideLevelDev("polD");
}

function showLevelDev(_mlevelId) {
    var thisLevel = document.getElementById(_mlevelId);

	if ( thisLevel.style.display == "none") {
		thisLevel.style.display = "block";
    
		}
	else {
		hideLevelDev( _mlevelId);
		}
	}