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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:

https://i.stack.imgur.com/Xwer8.png

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; */ }

header: sized to content
(but is it really?)
main content: fills remaining space
x
x
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footer: fixed height in px

Fiddle:

http://jsfiddle.net/7yLFL/1/ (working, with small content)

http://jsfiddle.net/7yLFL/ (broken, with larger content)

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:

Make a div fill the height of the remaining screen space

Fill remaining vertical space - only CSS

Have a div to fill out the remaining height/width of a container when sharing it with another div?

Make nested div stretch to 100% of remaining container div height

How can I make my flexbox layout take 100% vertical space?

etc

Seems to be working as expected on the fiddle.
Yes, you need to uncomment the rest of the
's content to see how it breaks. Maybe I should have linked the broken version. Sorry.
I have added both versions to the question now.
I see what you mean now.

G
G-Cyrillus

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*/ }

header: sized to content
(but is it really?)
main content: fills remaining space
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footer: fixed height in px

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; }

header: sized to content
(but is it really?)
main content: fills remaining space
x
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footer: fixed height in px


What if we want section to have a 100% height?
@PaulTotzke Then it is morelike another question , you just need to set height to 100%. As usual , parents needs an height set/usable, else we have the classic 100% of 'null' example for code above : html,body,section {height:100%;} where section is direct child of body jsfiddle.net/7yLFL/445 this gives a header and footer fixed.
@GCyrillus Thank you. I didn't realize html, body AND the wrapper all had to have a set size.
Thanks for the "min-height has its purpose". I was wondering why it didn't work, using height for fixed elements.
Had an issue with this solution in firefox. I rectified it by changing flex: 1 to flex-grow: 1. Thanks for the solution!
g
gamozzii

The example below includes scrolling behaviour if the content of the expanded centre component extends past its bounds. Also the centre component takes 100% of remaining space in the viewport.

jsfiddle here

html, body, .r_flex_container{
    height: 100%;
    display: flex;
    flex-direction: column;
    background: red;
    margin: 0;
}
.r_flex_container {
    display:flex;
    flex-flow: column nowrap;
    background-color:blue;
}

.r_flex_fixed_child {
    flex:none;
    background-color:black;
    color:white;

}
.r_flex_expand_child {
    flex:auto;
    background-color:yellow;
    overflow-y:scroll;
}

Example of html that can be used to demonstrate this behaviour

<html>
<body>
    <div class="r_flex_container">
      <div class="r_flex_fixed_child">
        <p> This is the fixed 'header' child of the flex container </p>
      </div>
      <div class="r_flex_expand_child">
            <article>this child container expands to use all of the space given to it -  but could be shared with other expanding childs in which case they would get equal space after the fixed container space is allocated. 
Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium quis, sem. Nulla consequat massa quis enim. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. In enim justo, rhoncus ut, imperdiet a, venenatis vitae, justo. Nullam dictum felis eu pede mollis pretium. Integer tincidunt. Cras dapibus. Vivamus elementum semper nisi. Aenean vulputate eleifend tellus. Aenean leo ligula, porttitor eu, consequat vitae, eleifend ac, enim. Aliquam lorem ante, dapibus in, viverra quis, feugiat a, tellus. Phasellus viverra nulla ut metus varius laoreet. Quisque rutrum. Aenean imperdiet. Etiam ultricies nisi vel augue. Curabitur ullamcorper ultricies nisi. Nam eget dui. Etiam rhoncus. Maecenas tempus, tellus eget condimentum rhoncus, sem quam semper libero, sit amet adipiscing sem neque sed ipsum. Nam quam nunc, blandit vel, luctus pulvinar, hendrerit id, lorem. Maecenas nec odio et ante tincidunt tempus. Donec vitae sapien ut libero venenatis faucibus. Nullam quis ante. Etiam sit amet orci eget eros faucibus tincidunt. Duis leo. Sed fringilla mauris sit amet nibh. Donec sodales sagittis magna. Sed consequat, leo eget bibendum sodales, augue velit cursus nunc,
            </article>
      </div>
      <div class="r_flex_fixed_child">
        this is the fixed footer child of the flex container
        asdfadsf
        <p> another line</p>
      </div>

    </div>
</body>
</html>

This can be slightly simplified by removing html from the selector and appyling height: 100vh to body specifically: jsfiddle.net/pm6nqcqh/1
I did notice a difference between flex:auto and flex:1 on the expandable child. With flex:auto, other children seem to shrink when needed, with flex:1 they don't (in Chrome)
w
wuppie367

A more modern approach would be to use the grid property.

section { display: grid; align-items: stretch; height: 300px; grid-template-rows: min-content auto 60px; } header { background: tomato; } div { background: gold; overflow: auto; } footer { background: lightgreen; }

header: sized to content
(but is it really?)
main content: fills remaining space
x
x
x
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footer: fixed height in px


T
TylerH

Use the flex-grow property to the main content div and give the display: flex; to its parent;

body { height: 100%; position: absolute; margin: 0; } section { height: 100%; display: flex; flex-direction : column; } header { background: tomato; } div { flex: 1; /* or flex-grow: 1 */; overflow-x: auto; background: gold; } footer { background: lightgreen; min-height: 60px; }

header: sized to content
(but is it really?)
main content: fills remaining space
x
x
x
x
x
x
x
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footer: fixed height in px


Is there any other solution to this problem (where section height isn't fixed?) rather than using position: absolute?
@ben If you know the height of the element. Then you can avoid using position: absolute; . https://jsfiddle.net/xa26brzf/
d
david

This is the simplest example that I can think of. The key is

Parent is display:flex Child has flex-grow:1 Parent MUST have height specified. If you specify height:100% on a parent div, then remember, the parent exists in a and you'll see the body isn't 100% unless you add height:100% on the body too.

http://jsfiddle.net/Ljbzsmvf/2/

div#parent { height: 300px; display: flex; flex-direction: column; } div#child { border: thin solid red; flex-grow: 1; }

Parent
Child


m
mPrinC

Here is the codepen demo showing the solution:

Demo - Fill remaining vertical space with CSS using display:flex

Important highlights:

all containers from html, body, ... .container, should have the height set to 100%

introducing flex to ANY of the flex items will trigger calculation of the items sizes based on flex distribution: if only one cell is set to flex, for example: flex: 1 then this flex item will occupy the remaining of the space if there are more than one with the flex property, the calculation will be more complicated. For example, if the item 1 is set to flex: 1 and the item 2 is se to flex: 2 then the item 2 will take twice more of the remaining space NOT TRUE: the item 2 will be twice larger than the item 1 check more about the concept of the remaining space: https://developer.mozilla.org/en-US/docs/Web/CSS/flex-grow

if only one cell is set to flex, for example: flex: 1 then this flex item will occupy the remaining of the space

if there are more than one with the flex property, the calculation will be more complicated. For example, if the item 1 is set to flex: 1 and the item 2 is se to flex: 2 then the item 2 will take twice more of the remaining space NOT TRUE: the item 2 will be twice larger than the item 1 check more about the concept of the remaining space: https://developer.mozilla.org/en-US/docs/Web/CSS/flex-grow

NOT TRUE: the item 2 will be twice larger than the item 1

check more about the concept of the remaining space: https://developer.mozilla.org/en-US/docs/Web/CSS/flex-grow

Main Size Property depends on the value of the flex-direction property in our case height is just a preferred size it will be overwritten in the presence of flex property: https://www.w3.org/TR/css-flexbox-1/#propdef-flex When a box is a flex item, flex is consulted instead of the main size property to determine the main size of the box min-* and max-* will be respected

depends on the value of the flex-direction property

in our case height is just a preferred size

it will be overwritten in the presence of flex property: https://www.w3.org/TR/css-flexbox-1/#propdef-flex When a box is a flex item, flex is consulted instead of the main size property to determine the main size of the box

When a box is a flex item, flex is consulted instead of the main size property to determine the main size of the box

min-* and max-* will be respected