#container { width: 100px; height: 100px; position: relative;}#navi,#infoi { width: 100%; height: 100%; position: absolute; top: 0; left: 0;}#infoi { z-index: 10;}<div id="container"> <div id="navi">a</div> <div id="infoi"> <img src="https://appharbor.com/assets/images/stackoverflow-logo.png" height="20" width="32" />b </div></div>我建议使用来了解
position: relative和子元素
position: absolute。
