if (client.environment=="Macintosh") document.write('<link rel="stylesheet" type="text/css" href="mac.css">');
     else if (client.environment=="Windows")
     {
          if (client.name=="IE")document.write('<link rel="stylesheet" type="text/css" href="win_ie.css">');
          else if ((client.name=="Netscape")&&(client.version<5))document.write('<link rel="stylesheet" type="text/css" href="win_ns.css">');
          else if ((client.name=="Netscape")&&(client.version>=5))document.write('<link rel="stylesheet" type="text/css" href="win_ns6.css">');
     }
     else document.write('<link rel="stylesheet" type="text/css" href="win_ie.css">');