css/css-flexbox/percentage-widths-001.html

<!DOCTYPE html>
<title>CSS Test: Absolutely positioned children of flexboxes</title>
<link rel="author" title="Google Inc." href="http://www.google.com/">
<link rel="help" href="https://drafts.csswg.org/css-flexbox/#definite-sizes">
<link rel="match" href="percentage-widths-001-ref.html">
<meta name="assert" content="Checks that we correctly size percentage-sized
children of absolute-positioned flex boxes">
<style>
body {
  position: relative;
  width: 600px;
  height: 800px;
}

#container {
  background-color: red;
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  display: flex;
  flex-direction: row;
}

#top-bar {
  background-color: green;
  width: 20%;
}

#content {
  background-color: blue;
  flex-basis: 100%;
}
</style>


<div id="container">
  <div id="top-bar">
  Tests that percentage widths get resolved correctly when the flexbox is
  </div>
  <div id="content">
  absolutely positioned without an explicit width. You should see no red.
  </div>
</div>