var old_layer_index = 0;
var classification_length = 0;

	function show_mlayer(index) {

		var now_winwidth = document.body.clientWidth;
		var left_margin  = 0;
		if (now_winwidth > 1024) {
			left_margin = (now_winwidth-1024)/2;
		}  
		var layer_name = "div"+index;
		var top_start = 217; 
		var left_start = 230;
		var layer_interval = 33;

		if (old_layer_index != 0 && old_layer_index != index) {
			var old_layer_name = "div"+old_layer_index;
			document.all[old_layer_name].style.visibility = "hidden";
		}

		old_layer_index = index;
		hide_mlayer_exclusive(index);
		document.all[layer_name].style.top = top_start + (index-1)*layer_interval;
		document.all[layer_name].style.left = left_margin + left_start;
		document.all[layer_name].style.visibility = "visible";

	}
	function hide_mlayer_exclusive(index) {
		for (var i = 1; i <= classification_length; i++) {
			if (i != index) document.all["div"+i].style.visibility = "hidden";

		}
	}
	function hide_mlayer(index) {
		var layer_name = "div"+index;
		document.all[layer_name].style.visibility = "hidden";

	}