Answers for "make element be positioned behind its parent, but in front of its grandparent"

make element be positioned behind its parent, but in front of its grandparent

<div class="grandparent" style="position: relative; z-index: 1;">
    <div class="parent">
        <div class="element" style="position: absolute; z-index: -1"></div>
    </div>
</div>

make element be positioned behind its parent, but in front of its grandparent

<div class="div1" style="position: relative; z-index:1;">
    <div class="div2" style="position: static;">
        <div class="div3" style="position: relative; z-index: -1;"></div>
    </div>
</div>