CSS div动态居中
<html> <head> <style type="text/css"> .box { width: 200px; height: 200px; border: 1px solid #000; position: fixed; left: 50%; top: 50%; margin-left: -100px; margin-top: -100px; _position: absolute; _top: expression(eval(document.documentElement.clientHeight/2+document.documentElement.scrollTop;)); _left: expression(eval(document.documentElement.clientWidth/2+document.documentElement.scrollLeft;)); } </style> </head> <body> <div class="box"></div> </body> </html>