Javascript/回転

var x = document.getElementById("rotateX");
var y = document.getElementById("rotateY");
var deg = 0;
window.onload = function rotate(){
	deg += 6;
	if(deg == 360){
		deg = 0;
	}
	if((0 <= deg && deg <90) || (270 <= deg && deg < 360)){
		x.className = "black";
		y.style.color = "#222";
	} else {
		x.className = "gray";
		y.style.color = "#bbb";
	}
	x.style.transform = "rotateX(" + deg + "deg)";
	y.style.transform = "rotateY(" + deg + "deg)";
	setTimeout(function(){
		rotate()
		},30);
}