1HTML代碼給出了內(nèi)層的3個div沿腰，顯示的數(shù)字即為z-index數(shù)值
<divclass="outer">
????<divclass="con1">99</div>
????<divclass="con2">999</div>
????<divclass="con3">9</div>
</div
2添加css樣式官研，注意內(nèi)層div的定位方式為relative藻治，并且分別設(shè)置了z-index數(shù)值
div.outer{width:350px;height:350px;padding:10px;border:1pxsolidgreen;}
div.outer?div{width:200px;height:200px;padding:05px;color:white;font-size:20px;position:relative;}
div.con1{background:red;top:20px;left:20px;z-index:99;}
div.con2{background:green;top:-100px;left:0px;z-index:999;}
div.con3{background:blue;top:-250px;right:-100px;text-align:right;z-index:9;
