Code with pure CSS to center the top, bottom, and left

<Br/> <style type = "text/CSS"> # box {width: 600px; Height: 400px; Border: 1px solid red ;}# box {position: static; * position: relative; display: Table; * display: block;} # Box-middle {position: static; * position: absolute; display: Table-cell; * display: block; * Top: 50%; Vertical-align: middle; * vertical-align: auto;} # Box-inner {position: relative; top:-50%; Background-color: blue; margin: 0 auto; width: 200px; Height: 100px ;}</style> content <p>
[Ctrl + A select all Note: If you need to introduce external JS, You need to refresh it to execute]

Finally, I saw this abnormal IE7, like fog and rain, like the wind, the CSS hack of the IE series: * HTML it recognizes; Firefox's CSS hack: HTML> body, # ID [ID], HTML [xmlns] Div, and so on. How can this problem be solved!
Finally, it was solved through invincible!