<div style="width: 100px;">
    <div id="first-line-element" style="display:inline-block; width: 100px; height: 50px; background-color: blue;"></div>
    <div style="float: left; width: 50px; height: 50px; background-color: red;">
        <div id="target" style="width: 50px; height: 50px; background-color: green; display: none;"></div>
    </div>
    <br>
    <img>
</div>
<script>
    document.body.offsetTop;
    document.getElementById("first-line-element").style.textAlign = "right";
    document.getElementById("target").style.display = "";
</script>