<!DOCTYPE HTML> <!-- Any copyright is dedicated to the Public Domain. http://creativecommons.org/publicdomain/zero/1.0/ --> <html><head> <meta charset="utf-8"> <title>Reference: margin:auto on grid abs.pos. child</title> <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1107783"> <style type="text/css"> div { display: block; position: relative; grid-template-columns: 100px; grid-template-rows: 100px; width: 100px; height: 100px; border: 1px solid; } span { display: block; position: absolute; background: lime; width: 20px; height: 20px; margin: 5px 7px 11px 13px; top:0; left:0; right:0; bottom:0; } </style> </head> <body> <div><span style="margin-left:auto"></span></div> <div><span style="margin-right:auto"></span></div> <div><span style="margin-left:auto; margin-right:auto"></span></div> <div><span style="margin-top:auto"></span></div> <div><span style="margin-bottom:auto"></span></div> <div><span style="margin-top:auto; margin-bottom:auto"></span></div> <div><span style="margin:auto"></span></div> </body> </html>