function fuc_environment() {
	var userAgent = navigator.userAgent.toLowerCase();
	
	this.isWin   = (userAgent.indexOf('win') != -1);
	this.isMac   = (userAgent.indexOf('mac') != -1);
	this.isUnix  = (userAgent.indexOf('unix') != -1 || userAgent.indexOf('linux') != -1 || userAgent.indexOf('sunos') != -1 || userAgent.indexOf('bsd') != -1 || userAgent.indexOf('x11') != -1);
	
	if ((userAgent.indexOf("msie") != -1) && (userAgent.indexOf("opera") == -1) && (userAgent.indexOf("webtv") == -1)) {
		var version = parseInt(navigator.appVersion);
		if (version >= 4) {
			version = parseInt(userAgent.substring(userAgent.indexOf('msie ') + 5));
		}
		this.ltIE7 = (version < 7);
		this.isIE7 = (version == 7);
	} else {
		this.isFF = (userAgent.indexOf("firefox") != -1);
		this.isOpera = (userAgent.indexOf("opera") != -1); 
	}
}

var environment = new fuc_environment();