Z-index site in use with position: absolute property of the div, to achieve special effects, no problems under IE8 IE9 CHROME FIREFOX, except IE6 IE7 layer shifted to the right side of the page phenomenon.
After a review of all kinds of information, try to use positon:. Relative settings of the parent layer, still need to find invalid after current position: absolute div layer of set top: 0, left: 0 property, the problem was solved.
Reproduced in: https: //www.cnblogs.com/caly/archive/2011/12/16/2290332.html