function getElementsByClassName(className, tag, elm){
	var testClass = new RegExp("(^|\\s)" + className + "(\\s|$)");
	var tag = tag || "*";
	var elm = elm || document;
	var elements = (tag == "*" && elm.all)? elm.all : elm.getElementsByTagName(tag);
	var returnElements = [];
	var current;
	var length = elements.length;
	for(var i=0; i<length; i++){
		current = elements[i];
		if(testClass.test(current.className)){
			returnElements.push(current);
		}
	}
	return returnElements;
}

function show(panel) {
    try {
        if ($) {
            $('*[id^=pnl_]').css('display', 'none');
        }
    } catch (e) {
        document.getElementById("pnl_keyfeatures").style.display = "none";
        document.getElementById("pnl_contents").style.display = "none";
        document.getElementById("pnl_specs").style.display = "none";
        document.getElementById("pnl_accessories").style.display = "none";
        document.getElementById("pnl_marketing").style.display = "none";
        document.getElementById("pnl_assets").style.display = "none";
    }
    document.getElementById("pnl_"+panel).style.display = "block";
}

function spec(spec_name) {
    show("specs");
    location.hash = spec_name;
}