$(document).ready(function(){

	$(".menu-list").each(function(){
		var imgSwitch = $("img.open", $(this));
		var openList = $("ul.open-list", $(this));
	
    $(imgSwitch).toggle(
      function () {
        $(openList).css("display", "block")
        $(this).attr("src", $(this).attr("src").replace("_plus", "_minus"));
      },
      function () {
        $(openList).css("display", "none")
        $(this).attr("src", $(this).attr("src").replace("_minus", "_plus"));
      }
    );
	
	});

  });