if(navigator.userAgent.indexOf("Mac")!=-1){
document.write("<META http-equiv=\"Content-Style-Type\" content=\"text/css\"><LINK rel=\"stylesheet\" href=\"style_mac.css\" type=\"text/css\">");
}else {
document.write("<META http-equiv=\"Content-Style-Type\" content=\"text/css\"><LINK rel=\"stylesheet\" href=\"style_win.css\" type=\"text/css\">");
}