function on_button()
	{
		var str = document.getElementById('scroll_button_img').src;
		if(str.lastIndexOf("mages/scroll_button2.jpg") == -1){
			document.getElementById('scroll_button_img').src = "images/scroll_button1.jpg";
		}
	}

	function out_button()
	{
		var str = document.getElementById('scroll_button_img').src;
		if(str.lastIndexOf("mages/scroll_button2.jpg") == -1){
			document.getElementById('scroll_button_img').src = "images/scroll_button0.jpg";
		}
	}

	function changeImg()
	{
		var str = document.getElementById('scroll_button_img').src;
		if(str.lastIndexOf("mages/scroll_button2.jpg") != -1){
			window.setTimeout(function(){document.getElementById('scroll_button_img').src = "images/scroll_button1.jpg"},600);
			document.getElementById('left_home_top_img').src = "images/left_home_top_1.jpg";
		}
		else{
			document.getElementById('scroll_button_img').src = "images/scroll_button2.jpg";
			document.getElementById('left_home_top_img').src = "images/left_home_top_2.jpg";
		}
	}