cssflexbox

How can I make Flexbox children 100% height of their parent?

I'm trying to fill the vertical space of a flex item inside a Flexbox.

.container {
  height: 200px;
  width: 500px;
  display: flex;
  flex-direction: row;
}
.flex-1 {
  width: 100px;
  background-color: blue;
}
.flex-2 {
  position: relative;
  flex: 1;
  background-color: red;
}
.flex-2-child {
  height: 100%;
  width: 100%;
  background-color: green;
}
<div class="container">
  <div class="flex-1"></div>
  <div class="flex-2">
    <div class="flex-2-child"></div>
  </div>
</div>

And here's the JSFiddle

flex-2-child doesn't fill the required height except in the two cases where:

  1. flex-2 has a height of 100% (which is weird because a flex item has a 100% by default + it is buggy in Chrome)
  2. flex-2-child has a position absolute which is also inconvenient

This doesn't work in Chrome or Firefox currently.

Solution

  • Use align-items: stretch

    Similar to David Storey's answer, my workaround is:

    .flex-2 {
    display: flex;
    align-items: stretch;
}

    Note that height: 100% must be removed from the child component (see comments).

    Alternatively to align-items, you can use align-self just on the .flex-2-child item you want stretched.