About the HTML and body height login Page The login box is always centered vertically horizontally in the page

Html

CSS commentary, the horizontal center is not much to say, to Div.login_wrap set a width, and then margin:0 Auto; But this is done here, using the two-layer div outer layer using margin:0 auto, first to the outer horizontal center, and then the inside a div using absolute positioning, the code is as follows.

HTML, body{height:100%; margin:0px;padding:0px; min-width:1200px;}

. login_wrap{width:960px;height:inherit;position:relative;margin:0 auto;}

. login_box{width:400px; Background-color:rgba (0,0,0,0.3); height:400px;position:absolute;left:50%;top:50%; margin:-200px 0 0-200px;}

Effect

About the HTML and body height login Page The login box is always centered vertically horizontally in the page