window.onload = function() {
	var company_status;
	var ir_status;
	var contact_status;
	
	var nav_company    = document.getElementById("company");
	var nav_ir_information         = document.getElementById("ir");
	var nav_contact    = document.getElementById("contact");
	
	init();
	
	nav_company.firstChild.onclick = function() {
		showMenu(nav_company, company_status);
		company_status = !company_status;
	}
	nav_ir_information.firstChild.onclick = function() {
		showMenu(nav_ir_information, ir_status);
		ir_status = !ir_status;
	}
	nav_contact.firstChild.onclick = function() {
		showMenu(nav_contact, contact_status);
		contact_status = !contact_status;
	}
	
	function init() {
		var URIs = new Array(
			"company",
			"ir_information",
			"contact"
		);
		var thisURI = new String(window.self.location);
		for (var i = 0; i < URIs.length; i++) {
			if (thisURI.search(new RegExp(URIs[i], "i")) != -1) {
				eval(URIs[i] + "_status = true");
				eval("nav_" + URIs[i] + '.getElementsByTagName("ul")[0].style.display = "block"');
			} else {
				eval(URIs[i] + "_status = false");
				eval("nav_" + URIs[i] + '.getElementsByTagName("ul")[0].style.display = "none"');
			}
		}
	}
	
	function showMenu(node, val) {
		if (val) {
			node.getElementsByTagName("ul")[0].style.display = "none";
		} else {
			node.getElementsByTagName("ul")[0].style.display = "block";
		}
	}
}