window.onload=init;

function init(){
	setButton();
}

function setButton(){
	setBtn("karaoke");
	setBtn("shop");
	setBtn("rental");
}

function setBtn(id){
	menues = document.getElementById(id).getElementsByTagName('a');
	for (var i=1; i<menues.length; i++){
		menues[i].style.visibility = "hidden";		
	}	
	document.getElementById(id).onmouseover = function(){
		var menues = document.getElementById(id).getElementsByTagName('a');
		for (var i=1; i<menues.length; i++){
			menues[i].style.visibility = "visible";
		}
	}
	document.getElementById(id).onmouseout = function(){
		var menues = document.getElementById(id).getElementsByTagName('a');
		for (var i=1; i<menues.length; i++){		
			menues[i].style.visibility = "hidden";
		}
	}
}