function goto(mmain) {
  
  //alert(mmain);
  
  //footer連結 
  if (mmain=="privacy") { window.open("privacy.php","_self"); }
  if (mmain=="service") { window.open("servicepolicy.php","_self"); }
  if (mmain=="sitemap") { window.open("sitemap.php","_self"); }
  if (mmain=="contact") { window.open("contact_us.php","_self"); }
  if (mmain=="lang") { window.open("en/index.php","_self"); }
  if (mmain=="y5") { window.open("http://www.y5works.com","_blank"); }
  
  //產品連結
  if (mmain=="pro1") { window.open("product.php?id=1","_self"); }
  if (mmain=="pro2") { window.open("product.php?id=3","_self"); }
  if (mmain=="pro3") { window.open("product.php?id=2","_self"); }
  if (mmain=="pro4") { window.open("product.php?id=4","_self"); }
  if (mmain=="pro5") { window.open("product.php?id=6","_self"); }
  if (mmain=="pro6") { window.open("product.php?id=8","_self"); }
  if (mmain=="pro7") { window.open("product.php?id=10","_self"); }
  if (mmain=="pro8") { window.open("product.php?id=13","_self"); }
  
};