var os = navigator.platform;
var brName = navigator.appName.charAt(0);
var brVer = navigator.appVersion.charAt(0);
var agent = navigator.userAgent;

function set_css(pos){
if(os == "Win32"){
if((brName == "N") && (brVer >= 4) && (brVer < 5)){ // WIN NS4以上NS6以下
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/win_nc.css">';
}
else if((brName == "N") && (brVer >= 5)) {	// WIN NS6以上
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/win_nc6.css">' ;
}
else if((brName == "M") && (brVer >= 4)) {	// WIN IE4以上
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/win_ie.css">' ;
}
else{	// WINの上記以外
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/basic.css">' ;
}
}
else if(os == "MacPPC" || os == "Mac68K"){
if((brName == "N") && (brVer >= 4) && (brVer < 5)){ // MAC NS4以上NS6以下
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/mac_nc.css">' ;
}
else if((brName == "N") && (brVer >= 5)){	// MAC NS6以上
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/mac_nc6.css">' ;
}
else if((brName == "M") && (brVer >= 4)) {	// MAC IE4以上
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/mac_ie.css">' ;
}
else{	// MACの上記以外
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/basic.css">' ;
}
}
else{	// このスクリプトが動作するWIN、MAC以外の環境
cssSrc = '<LINK REL="stylesheet" TYPE="text/css" HREF="'+pos+'css/basic.css">' ;
}
document.write( cssSrc ) ;
}