if (mtDropDown.isSupported()) {
  var ms = new mtDropDownSet(mtDropDown.direction.down, -15, 58, mtDropDown.reference.bottomLeft);

  var menu2 = ms.addMenu(document.getElementById("menu2"));
  menu2.addItem("&nbsp;&nbsp;视频会议&nbsp;&nbsp;", "sphy.html");
  menu2.addItem("&nbsp;&nbsp;综合布线系统&nbsp;&nbsp;", "zhbxxt.html");
  menu2.addItem("&nbsp;&nbsp;LAN&nbsp;/&nbsp;WAN设备&nbsp;&nbsp;", "lanwansb.html");
  menu2.addItem("&nbsp;&nbsp;集团采购&nbsp;&nbsp;", "jtcg.html");
  
  var menu3 = ms.addMenu(document.getElementById("menu3"));
  menu3.addItem("&nbsp;&nbsp;协同办公&nbsp;&nbsp;", "xtbg.html");
  menu3.addItem("&nbsp;&nbsp;行业软件&nbsp;&nbsp;", "hyrj.html");
  menu3.addItem("&nbsp;&nbsp;运营维护&nbsp;&nbsp;", "yywh.html");
  
  var menu4 = ms.addMenu(document.getElementById("menu4"));
  menu4.addItem("&nbsp;&nbsp;郑州铁路公务检测中心&nbsp;&nbsp;", "zztlgwjczx.html");
  menu4.addItem("&nbsp;&nbsp;交通部东海救助局&nbsp;&nbsp;", "jtbdhjzj.html");
  menu4.addItem("&nbsp;&nbsp;西安铁路局&nbsp;&nbsp;", "xatlj.html");
  menu4.addItem("&nbsp;&nbsp;阿尔卡特内部OA管理系统&nbsp;&nbsp;", "shnhzsj.html");
  menu4.addItem("&nbsp;&nbsp;TBI日系企业招聘协同管理系统&nbsp;&nbsp;", "rixi.html");
    
 mtDropDown.renderAll();
 }