<div class="div green" id="div"></div>
body {
  padding: 20px;
}
.div {
    width: 30px;
    height: 20px;
    position: relative;
}

.green {
    background-color: green;
}

.red {
    background-color: red;
}

.blue {
    background-color: blue;
}
function moveDiv(div, fps) {
    var left = 0;
    var param = 1;
    function loop () {
        update();
        draw();
    }
    function update() {
        left += param * 2;
        if (left > 300) {
            left = 300;
            param = -1;
        } else if (left < 0) {
            left = 0;
            param = 1;
        }
    }
    function draw() {
        div.style.left = left + "px";
    }
    setInterval(loop, 1000 / fps);
}
moveDiv(document.getElementById("div"), 60);

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