<div style="position:relative;">
<div style="position:absolute;z-index:100;width:100px;height:100px;background:red;"></div>
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<div style="position:relative;">
<div style="position:absolute;z-index:10;width:20px;height:20px;background:black;"></div>
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<div style="position:relative;z-index:2;">
<div style="position:absolute;z-index:100;width:100px;height:100px;background:red;"></div>
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<div style="position:relative;z-index:1;">
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