$(document).ready(function() {
	// 小ボックス
	$("#sub .course dt").hover(function(){
		$(this).css("cursor","pointer"); 
	},function(){
		$(this).css("cursor","default"); 
	});
	$("#sub .course dd").css("display","none");
	$("#sub .course dt").click(function(){
		$(this).next().slideToggle("fast");
		var arrow = $(this).css('background-image');
		var a_arrow = arrow.replace(/plus/, "minus");
		if(arrow.match("plus")){
			var a_arrow = arrow.replace(/plus/, "minus");
			$(this).css('background-image', a_arrow);
		}else{
			var a_arrow = arrow.replace(/minus/, "plus");
			$(this).css('background-image', a_arrow);
		}
	});
});