<!DOCTYPE html> <html> <head> <title>CSS 2.1 Test Suite: Test for z-ordering of inline-block</title> <link rel="author" title="L. David Baron" href="https://dbaron.org/" /> <link rel="author" title="Mozilla Corporation" href="http://mozilla.com/" /> <link rel="help" href="http://www.w3.org/TR/CSS21/zindex.html#painting-order" /> <style type="text/css"> div { width: 2em; height: 1em; } span { display:inline-block; vertical-align: top; width: 2em; height: 1em; } span span { display: block; background: green; } div#after { margin-top: -1em; background: red; } </style> </head> <body> <div><span><span> </span></span></div> <div id="after"> </div> </body> </html>