<div style="position: relative;">
    <div style="width: 100px; height: 100px; background-color: red;"></div>
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        <div id="inner" style="width: 100px; height: 100px; background-color: green;"></div>
    </div>
</div>
<script>
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    {
        document.getElementById("inner").style.visibility = "visible";
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        document.body.offsetTop;
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        test();
    } else
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</script>