<!DOCTYPE html> <!-- Any copyright is dedicated to the Public Domain. http://creativecommons.org/publicdomain/zero/1.0/ --> <!-- Reference case, using inline-block instead of inline-flex, and with the inline-blocks manually positioned with "vertical-align:top" and margin-top. --> <html> <head> <title>CSS Reftest Reference</title> <link rel="author" title="Daniel Holbert" href="mailto:dholbert@mozilla.com"> <meta charset="utf-8"> <link rel="stylesheet" type="text/css" href="support/ahem.css" /> <style> body { margin: 0; font: 20px Ahem; line-height: 20px; /* Baseline is 0.8em = 16px from top */ } .flexContainer { display: inline-block; background: lightblue; } .smallFont { font-size: 10px; line-height: 10px; /* Baseline is 0.8em = 8px from top */ } .bigFont { font-size: 20px; line-height: 20px; /* Baseline is 0.8em = 16px from top */ } * { vertical-align: top } </style> </head> <body> a <div class="flexContainer" style="margin-top: 8px"> <div class="smallFont">b</div ><div class="bigFont">c</div> </div> <div class="flexContainer"> <div class="bigFont">d</div ><div class="smallFont">e</div> </div> </body> </html>