var isMac = navigator.userAgent.toLowerCase().indexOf("mac") !=-1;
var isSafari = navigator.userAgent.toLowerCase().indexOf("safari") !=-1;


if (isMac) {
	document.write('	<link rel=\"stylesheet\" type=\"text/css\" href=\"/css/mac.css\" media=\"all\" />');
}

if (isSafari) {
	document.write('	<link rel=\"stylesheet\" type=\"text/css\" href=\"/css/safari.css\" media=\"all\" />');
}

function clear_signup_field() {
if (document.signup_form.signup_field.value == "enter email address")
	document.signup_form.signup_field.value = "";
}