Does CSS Grid have a flex-grow function?

Ced picture Ced · Aug 24, 2017 · Viewed 19.7k times · Source

Is there an analog to flex-grow for the grid property ?

I'd like my grid areas to accomodate the content they receive but have some areas take more place than others like flex-grow for flex.

Practically, in the example below I'd like

  • the turquoise to be invisible because it accomodates its content.
  • The footer to be invisible as well because it has no content.
  • The middle section take the remaining of the page like flex-grow.

More practically, I'd like this code:

To act like this code:

.ctnr {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

.panel {
  flex-grow: 1;
  display: flex;
}

header {
  flex-grow: 0;
  background: turquoise;
}

nav {
  min-width: 10rem;
  background: grey
}

footer {
  background: yellow
}
<div class="ctnr">
  <header>hey</header>
  <div class="panel">
    <nav></nav>
    <main></main>
  </div>
  <footer></footer>
</div>

Without the div.panel and without adding any additional tag.

The reason I would like to do this, is a legitimate one, that extra div element is annoying me.

Answer

Michael Benjamin picture Michael Benjamin · Aug 25, 2017

CSS Grid offers the fr unit, which functions similarly to flex-grow.

While flex-grow distributes free space in the container among flex items, the fr unit distributes free space in the container among rows / columns.

From the spec:

7.2.3. Flexible Lengths: the fr unit

A flexible length or <flex> is a dimension with the fr unit, which represents a fraction of the free space in the grid container.

(Note that flex-grow is applied to flex items, while fr lengths are applied to grid containers.)

So in your grid, you have three rows:

  1. The first row is the header. You want the content to set its height. So its height is set to auto.

  2. The last row is the footer. You want the content to set its height. So its height is set to auto.

  3. The middle row contains the nav and main elements. You want this row to occupy all remaining vertical space. So its height is set to 1fr.

.ctnr {
  display: grid;
  grid-template-rows: auto 1fr auto;  /* key rule */
  grid-template-columns: 1fr 1fr;
  height: 100vh;
  grid-template-areas: "header header" 
                         "nav main" 
                       "footer footer";
}

header {
  grid-area: header;
  background: turquoise;
}

nav {
  grid-area: nav;
  background: grey;
}

main {
  grid-area: main;
  background: orange;
}

footer {
  grid-area: footer;
  background: yellow;
}

body {
  margin: 0;
}
<div class="ctnr">
  <header>header</header>
  <nav>nav</nav>
  <main>main</main>
  <footer>footer</footer>
</div>

jsFiddle demo