funtion that generate a red div and rotate it constantly dynamically

function change() {
    var b = document.getElementById("div1");
    b.style.transform = "rotate(30deg)";
    b.style.transitionDuration = "3s";
    setTimeout(change2, 3000);
}

function change2() {
    var b = document.getElementById("div1");
    b.style.transform = "rotate(0deg)";
    b.style.transitionDuration = "3s";
    setTimeout(change, 3000);
}