if(navigator.appName=="Netscape"){
  if(navigator.appVersion.indexOf("Mac")!=-1)
  document.write('<link rel="stylesheet" type="text/css" href="/bus/css/kosoku/mac_nn.css" title="fontproperty">');
  else if(navigator.appVersion.indexOf("Win")!=-1)
  document.write('<link rel="stylesheet" type="text/css" href="/bus/css/kosoku/win_nn.css" title="fontproperty">');
}
else if(navigator.appName=="Microsoft Internet Explorer"){
  if(navigator.appVersion.indexOf("Mac")!=-1)
  document.write('<link rel="stylesheet" type="text/css" href="/bus/css/kosoku/mac_ie.css" title="fontproperty">');
  else if(navigator.appVersion.indexOf("Win")!=-1)
  document.write('<link rel="stylesheet" type="text/css" href="/bus/css/kosoku/win_ie.css" title="fontproperty">');
}