function Browser() {
	var agent = navigator.userAgent;		// User Agent
	
	this.isIE = false;			// Internet Explorer
	this.isOP = false;			// Opera
	this.isNS = false;			// Netscape/Mozilla
	this.isSF = false;			// Safari
	this.Win  = false;			// OS is Windows
	this.Mac  = false;			// OS is Mac
	
	// OS is Windows
	if(agent.indexOf("Windows") >= 0) {
		this.Win = true;
	// OS is Macintosh
	} else if(agent.indexOf("Mac") >= 0) {
		this.Mac = true;
	}
	
	// Case of Opera
	if((i = agent.indexOf("Opera")) >= 0) {
		this.isOP = true;
	// Case of Safari
	} else if((i = agent.indexOf("Safari")) >= 0) {
		this.isSF = true;
	// Case of Netscape
	} else if((i = agent.indexOf("Netscape6/")) >= 0) {
		this.isNS = true;
	// Case of treat any other Gecko Broser as Netscape
	} else if((i = agent.indexOf("Gecko")) >= 0) {
		this.isNS = true;
	// Case of Internet Explorer
	} else if((i = agent.indexOf("MSIE")) >= 0) {
		this.isIE = true;
	}
}

// ブラウザチェック
var browser = new Browser();

// CSSの書き出し
if(browser.isIE && browser.Win) {
	document.write('<link href="winie.css" rel="stylesheet" type="text/css">');
} else if(browser.isIE && browser.Mac) {
	document.write('<link href="macie.css" rel="stylesheet" type="text/css">');
} else if(browser.isNS) {
	document.write('<link href="nn.css" rel="stylesheet" type="text/css">');
} else if(browser.isSF) {
	document.write('<link href="safari.css" rel="stylesheet" type="text/css">');
} else {
	document.write('<link href="nn.css" rel="stylesheet" type="text/css">');
}