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Fill remaining vertical space with CSS using display:flex


In a 3-row layout:

  • the top row should be sized according to its contents
  • the bottom row should have a fixed height in pixels
  • the middle row should expand to fill the container

The problem is that as the main content expands, it squishes the header and footer rows:

Flexing Bad

section {
  display: flex;
  flex-flow: column;
  align-items: stretch;
  height: 300px;
}
header {
  flex: 0 1 auto;
  background: tomato;
}
div {
  flex: 1 1 auto;
  background: gold;
  overflow: auto;
}
footer {
  flex: 0 1 60px;
  background: lightgreen;
  /* fixes the footer: min-height: 60px; */
}
<section>
  <header>
    header: sized to content
    <br>(but is it really?)
  </header>
  <div>
    main content: fills remaining space<br>
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
    <!-- uncomment to see it break - ->
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
    <!-- -->
  </div>
  <footer>
    footer: fixed height in px
  </footer>
</section>

Fiddle:

I'm in the lucky situation that I can use the latest and greatest in CSS, disregarding legacy browsers. I thought I could use the flex layout to finally get rid of the old table-based layouts. For some reason, it's not doing what I want...

For the record, there are many related questions on SO about "filling the remaining height", but nothing that solves the problem I'm having with flex. Refs:


Solution

  • Make it simple : DEMO

    section {
      display: flex;
      flex-flow: column;
      height: 300px;
    }
    
    header {
      background: tomato;
      /* no flex rules, it will grow */
    }
    
    div {
      flex: 1;  /* 1 and it will fill whole space left if no flex value are set to other children*/
      background: gold;
      overflow: auto;
    }
    
    footer {
      background: lightgreen;
      min-height: 60px;  /* min-height has its purpose :) , unless you meant height*/
    }
    <section>
      <header>
        header: sized to content
        <br/>(but is it really?)
      </header>
      <div>
        main content: fills remaining space<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
        <!-- uncomment to see it break -->
        x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
        <!-- -->
      </div>
      <footer>
        footer: fixed height in px
      </footer>
    </section>

    Full screen version

    section {
      display: flex;
      flex-flow: column;
      height: 100vh;
    }
    
    header {
      background: tomato;
      /* no flex rules, it will grow */
    }
    
    div {
      flex: 1;
      /* 1 and it will fill whole space left if no flex value are set to other children*/
      background: gold;
      overflow: auto;
    }
    
    footer {
      background: lightgreen;
      min-height: 60px;
      /* min-height has its purpose :) , unless you meant height*/
    }
    
    body {
      margin: 0;
    }
    <section>
      <header>
        header: sized to content
        <br/>(but is it really?)
      </header>
      <div>
        main content: fills remaining space<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
        <!-- uncomment to see it break -->
        x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x
        <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>
        <!-- -->
      </div>
      <footer>
        footer: fixed height in px
      </footer>
    </section>