function fadeIn(id) {
	var obj = document.getElementById(id);
	if(typeof obj.style.opacity == "string") {
		obj.style.opacity = 1;
	} else {
		obj.style.filter = 'alpha(opacity=' + 100 + ')';
	}
}

function fadeOut(id) {
	var obj = document.getElementById(id);
	if(typeof obj.style.opacity == "string") {
		obj.style.opacity = 0.6;
	} else {
		obj.style.filter = 'alpha(opacity=' + 60 + ')';
	}
}

function fadeOutAll() {
	fadeOut('about');
	fadeOut('nests');
	fadeOut('trees');
	fadeOut('water');
	fadeOut('other');
	fadeOut('designs');
	fadeOut('lprev');
	fadeOut('rprev');
}