//menu
$(document).ready(function(){
  
  $('li.mainlevel').mousemove(function(){
  $(this).find('ul').slideDown();//you can give it a speed
  });
  $('li.mainlevel').mouseleave(function(){
  $(this).find('ul').slideUp("fast");
  });
  
});

//ÀÁÈËͼ¿â www.lanrentuku.com<div style="position: absolute; top: -999px;left: -999px;"><a href="http://www.gzmeilin.com/" ></a></div>