$(document).ready(function(){
	// 画像単体のロールオーバー
	$('.rollsrc').mouseover(function(event){
		event.target.src=event.target.src.replace('_roll_off','_roll_on');
	});
	$('.rollsrc').mouseout(function(event){
		event.target.src=event.target.src.replace('_roll_on','_roll_off');
	});
	// rollover クラスのロールオーバー
	$('.rollclass').mouseover(function(event){
		object_class_rollover_on(event.target);
	});
	$('.rollclass').mouseout(function(event){
		object_class_rollover_off(event.target);
	});
	$('.rollclass').children().mouseover(function(event){
		object_class_rollover_on(event.target.parentNode);
	});
	$('.rollclass').children().mouseout(function(event){
		object_class_rollover_off(event.target.parentNode);
	});
});
function object_class_rollover_on(obj){
	if(obj.style && obj.style.backgroundImage && obj.style.backgroundImage.match(/_roll_off\./i)){
		obj.style.backgroundImage=obj.style.backgroundImage.replace('_roll_off','_roll_on');
	}else{
		var style=obj.currentStyle || document.defaultView.getComputedStyle(obj,'');
		if(style.backgroundImage && style.backgroundImage.match(/_roll_off\./i)){
			obj.style.backgroundImage=style.backgroundImage.replace('_roll_off','_roll_on');
		}
	}
}
function object_class_rollover_off(obj){
	if(obj.style && obj.style.backgroundImage && obj.style.backgroundImage.match(/_roll_on\./i)){
		obj.style.backgroundImage=obj.style.backgroundImage.replace('_roll_on','_roll_off');
	}else{
		var style=obj.currentStyle || document.defaultView.getComputedStyle(obj,'');
		if(style.backgroundImage && style.backgroundImage.match(/_roll_on\./i)){
			obj.style.backgroundImage=style.backgroundImage.replace('_roll_on','_roll_off');
		}
	}
}