51help TIY
码：
<html> <head> <style type="text/css"> img.x { position:absolute; left:0px; top:0px; z-index:-1 } </style> </head> <body> <h1>题</h1> <img class="x" src="../i/eg_mouse.jpg" tppabs="http://www.51help.tk/i/eg_mouse.jpg" /> <p>默认的 z-index 是 0。Z-index -1 优先级。</p> </body> </html>
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