//　Macintosh           　->  MacOS
//　Windows95/98/NT/2000/XP  ->　Windows
//　UNIX                  ->　UNIX
function getOSType()
{
    var uAgent  = navigator.userAgent.toUpperCase();
    if (uAgent.indexOf("MAC") >= 0) return "MacOS";
    if (uAgent.indexOf("WIN") >= 0) return "Windows";
    if (uAgent.indexOf("X11") >= 0) return "UNIX";
    return "";
}

os      = getOSType();
if (os == "MacOS")   dirName = "0css/css002.css";
if (os == "Windows") dirName = "0css/css102.css";
if (os == "UNIX")    dirName = "0css/css002.css";
document.write("<link rel='stylesheet' href='"+dirName+"' type='text/css'>");