<!DOCTYPE html> <!-- Any copyright is dedicated to the Public Domain. http://creativecommons.org/publicdomain/zero/1.0/ --> <html> <head> <meta charset="utf-8"> <title>CSS Test: Testing min-height:auto</title> <link rel="author" title="Daniel Holbert" href="mailto:dholbert@mozilla.com"> <link rel="help" href="http://www.w3.org/TR/css-flexbox-1/#min-size-auto"> <link rel="match" href="flexbox-min-height-auto-002-ref.html"> <!-- This testcase tests the used value of "min-height:auto" (the property's initial value) on flex items in a vertical flex container. It's supposed to resolve to the smallest of: a) The used 'flex-basis' (taken from 'height'), if 'flex-basis' is at its initial value. b) The computed 'max-height' property c) If there's no intrinsic aspect ratio: the item's min-content height. d) If there is an intrinsic aspect ratio: the item's height derived from the ratio & constraints in the other dimension. We measure what the used value is by putting flex items in a small flex container, which will shrink its items down to their min-height. This test checks for situations where we should resolve the min-height as (d) above, with "constraints in the other dimension" being "min-width". --> <style> .flexbox { display: flex; flex-direction: column; max-width: 34px; /* Constrain the flex container's cross size. */ height: 1px; /* No available space; shrink flex items to min-height */ margin-right: 2px; /* (Just for spacing things out, visually) */ float: left; } .flexbox > * { /* Flex items have purple border: */ border: 2px dotted purple; /* Flex items have sizing constraint in cross axis: */ min-width: 30px; } </style> </head> <body> <!-- Check for min-height:auto resolving correctly when the smallest candidate value is: --> <!-- *** (d) (with intrinsic aspect ratio) The height derived from ratio and constraints in the other dimension *** --> <!-- First, with a larger candidate 'flex-basis' value (from 'height') --> <div class="flexbox"> <img style="height: 100px" src="support/solidblue.png" alt="blue square"> </div> <!-- ...and now with a larger explicit 'flex-basis' value (which shouldn't be considered for 'min-height:auto' anyway) --> <div class="flexbox"> <img style="flex-basis: 100px" src="support/solidblue.png" alt="blue square"> </div> <!-- ...and now with a smaller explicit 'flex-basis' value (which shouldn't be considered for 'min-height:auto' anyway) --> <div class="flexbox"> <img style="flex-basis: 10px" src="support/solidblue.png" alt="blue square"> </div> </body> </html>