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twbs--bootstrap/docs/4.0/utilities/flexbox.md

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---
layout: docs
title: Flexbox
description: Quickly manage the layout, alignment, and sizing of grid columns, navigation, components, and more with a full suite of responsive flexbox utilities. For more complex implementations, custom CSS may be necessary.
group: utilities
toc: true
---
## Enable flex behaviors
Apply `display` utilities to create a flexbox container and transform **direct children elements** into flex items. Flex containers and items are able to be modified further with additional flex properties.
{% example html %}
<div class="d-flex p-2 bd-highlight">I'm a flexbox container!</div>
{% endexample %}
{% example html %}
<div class="d-inline-flex p-2 bd-highlight">I'm an inline flexbox container!</div>
{% endexample %}
Responsive variations also exist for `.d-flex` and `.d-inline-flex`.
{% for bp in site.data.breakpoints %}
- `.d{{ bp.abbr }}-flex`
- `.d{{ bp.abbr }}-inline-flex`{% endfor %}
## Direction
Set the direction of flex items in a flex container with direction utilities. In most cases you can omit the horizontal class here as the browser default is `row`. However, you may encounter situations where you needed to explicitly set this value (like responsive layouts).
Use `.flex-row` to set a horizontal direction (the browser default), or `.flex-row-reverse` to start the horizontal direction from the opposite side.
{% example html %}
<div class="d-flex flex-row bd-highlight mb-3">
<div class="p-2 bd-highlight">Flex item 1</div>
<div class="p-2 bd-highlight">Flex item 2</div>
<div class="p-2 bd-highlight">Flex item 3</div>
</div>
<div class="d-flex flex-row-reverse bd-highlight">
<div class="p-2 bd-highlight">Flex item 1</div>
<div class="p-2 bd-highlight">Flex item 2</div>
<div class="p-2 bd-highlight">Flex item 3</div>
</div>
{% endexample %}
Use `.flex-column` to set a vertical direction, or `.flex-column-reverse` to start the vertical direction from the opposite side.
{% example html %}
<div class="d-flex flex-column bd-highlight mb-3">
<div class="p-2 bd-highlight">Flex item 1</div>
<div class="p-2 bd-highlight">Flex item 2</div>
<div class="p-2 bd-highlight">Flex item 3</div>
</div>
<div class="d-flex flex-column-reverse bd-highlight">
<div class="p-2 bd-highlight">Flex item 1</div>
<div class="p-2 bd-highlight">Flex item 2</div>
<div class="p-2 bd-highlight">Flex item 3</div>
</div>
{% endexample %}
Responsive variations also exist for `flex-direction`.
{% for bp in site.data.breakpoints %}
- `.flex{{ bp.abbr }}-row`
- `.flex{{ bp.abbr }}-row-reverse`
- `.flex{{ bp.abbr }}-column`
- `.flex{{ bp.abbr }}-column-reverse`{% endfor %}
## Justify content
Use `justify-content` utilities on flexbox containers to change the alignment of flex items on the main axis (the x-axis to start, y-axis if `flex-direction: column`). Choose from `start` (browser default), `end`, `center`, `between`, or `around`.
<div class="bd-example">
<div class="d-flex justify-content-start bd-highlight mb-3">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex justify-content-end bd-highlight mb-3">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex justify-content-center bd-highlight mb-3">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex justify-content-between bd-highlight mb-3">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex justify-content-around bd-highlight">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex justify-content-start">...</div>
<div class="d-flex justify-content-end">...</div>
<div class="d-flex justify-content-center">...</div>
<div class="d-flex justify-content-between">...</div>
<div class="d-flex justify-content-around">...</div>
{% endhighlight %}
Responsive variations also exist for `justify-content`.
{% for bp in site.data.breakpoints %}
- `.justify-content{{ bp.abbr }}-start`
- `.justify-content{{ bp.abbr }}-end`
- `.justify-content{{ bp.abbr }}-center`
- `.justify-content{{ bp.abbr }}-between`
- `.justify-content{{ bp.abbr }}-around`{% endfor %}
## Align items
Use `align-items` utilities on flexbox containers to change the alignment of flex items on the cross axis (the y-axis to start, x-axis if `flex-direction: column`). Choose from `start`, `end`, `center`, `baseline`, or `stretch` (browser default).
<div class="bd-example">
<div class="d-flex align-items-start bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex align-items-end bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex align-items-center bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex align-items-baseline bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex align-items-stretch bd-highlight" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex align-items-start">...</div>
<div class="d-flex align-items-end">...</div>
<div class="d-flex align-items-center">...</div>
<div class="d-flex align-items-baseline">...</div>
<div class="d-flex align-items-stretch">...</div>
{% endhighlight %}
Responsive variations also exist for `align-items`.
{% for bp in site.data.breakpoints %}
- `.align-items{{ bp.abbr }}-start`
- `.align-items{{ bp.abbr }}-end`
- `.align-items{{ bp.abbr }}-center`
- `.align-items{{ bp.abbr }}-baseline`
- `.align-items{{ bp.abbr }}-stretch`{% endfor %}
## Align self
Use `align-self` utilities on flexbox items to individually change their alignment on the cross axis (the y-axis to start, x-axis if `flex-direction: column`). Choose from the same options as `align-items`: `start`, `end`, `center`, `baseline`, or `stretch` (browser default).
<div class="bd-example">
<div class="d-flex bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="align-self-start p-2 bd-highlight">Aligned flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="align-self-end p-2 bd-highlight">Aligned flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="align-self-center p-2 bd-highlight">Aligned flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex bd-highlight mb-3" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="align-self-baseline p-2 bd-highlight">Aligned flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex bd-highlight" style="height: 100px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="align-self-stretch p-2 bd-highlight">Aligned flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="align-self-start">Aligned flex item</div>
<div class="align-self-end">Aligned flex item</div>
<div class="align-self-center">Aligned flex item</div>
<div class="align-self-baseline">Aligned flex item</div>
<div class="align-self-stretch">Aligned flex item</div>
{% endhighlight %}
Responsive variations also exist for `align-self`.
{% for bp in site.data.breakpoints %}
- `.align-self{{ bp.abbr }}-start`
- `.align-self{{ bp.abbr }}-end`
- `.align-self{{ bp.abbr }}-center`
- `.align-self{{ bp.abbr }}-baseline`
- `.align-self{{ bp.abbr }}-stretch`{% endfor %}
## Auto margins
Flexbox can do some pretty awesome things when you mix flex alignments with auto margins.
### With justify-content
Easily move all flex items to one side, but keep another on the opposite end by mixing `justify-content` with `margin-right: auto` or `margin-left: auto`.
{% example html %}
<div class="d-flex justify-content-end bd-highlight mb-3">
<div class="mr-auto p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex justify-content-start bd-highlight">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="ml-auto p-2 bd-highlight">Flex item</div>
</div>
{% endexample %}
### With align-items
Similarly, move one flex item to the top or bottom of a container by mixing `align-items`, `flex-direction: column`, and `margin-top: auto` or `margin-bottom: auto`.
{% example html %}
<div class="d-flex align-items-start flex-column bd-highlight mb-3" style="height: 200px;">
<div class="mb-auto p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
<div class="d-flex align-items-end flex-column bd-highlight mb-3" style="height: 200px;">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="mt-auto p-2 bd-highlight">Flex item</div>
</div>
{% endexample %}
## Wrap
Change how flex items wrap in a flex container. Choose from no wrapping at all (the browser default) with `.flex-nowrap`, wrapping with `.flex-wrap`, or reverse wrapping with `.flex-wrap-reverse`.
<div class="bd-example">
<div class="d-flex flex-nowrap bd-highlight">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex flex-nowrap">
...
</div>
{% endhighlight %}
<div class="bd-example">
<div class="d-flex flex-wrap bd-highlight">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex flex-wrap">
...
</div>
{% endhighlight %}
<div class="bd-example">
<div class="d-flex flex-wrap-reverse bd-highlight">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex flex-wrap-reverse">
...
</div>
{% endhighlight %}
{% example html %}
{% endexample %}
Responsive variations also exist for `flex-wrap`.
{% for bp in site.data.breakpoints %}
- `.flex{{ bp.abbr }}-nowrap`
- `.flex{{ bp.abbr }}-wrap`
- `.flex{{ bp.abbr }}-wrap-reverse`{% endfor %}
## Order
Change the _visual_ order of specific flex items with a handful of `order` utilities. We only provide options for making an item first or last, as well as a reset to use the DOM order. As `order` takes any integer value (e.g., `5`), add custom CSS for any additional values needed.
{% example html %}
<div class="d-flex flex-nowrap bd-highlight">
<div class="order-last p-2 bd-highlight">First flex item</div>
<div class="p-2 bd-highlight">Second flex item</div>
<div class="order-first p-2 bd-highlight">Third flex item</div>
</div>
{% endexample %}
Responsive variations also exist for `order`.
{% for bp in site.data.breakpoints %}
- `.order{{ bp.abbr }}-first`
- `.order{{ bp.abbr }}-last`
- `.order{{ bp.abbr }}-0`{% endfor %}
## Align content
Use `align-content` utilities on flexbox containers to align flex items *together* on the cross axis. Choose from `start` (browser default), `end`, `center`, `between`, `around`, or `stretch`. To demonstrate these utilities, we've enforced `flex-wrap: wrap` and increased the number of flex items.
**Heads up!** This property has no affect on single rows of flex items.
<div class="bd-example">
<div class="d-flex align-content-start flex-wrap bd-highlight mb-3" style="height: 200px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex align-content-start flex-wrap">
...
</div>
{% endhighlight %}
<div class="bd-example">
<div class="d-flex align-content-end flex-wrap bd-highlight mb-3" style="height: 200px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex align-content-end flex-wrap">...</div>
{% endhighlight %}
<div class="bd-example">
<div class="d-flex align-content-center flex-wrap bd-highlight mb-3" style="height: 200px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex align-content-center flex-wrap">...</div>
{% endhighlight %}
<div class="bd-example">
<div class="d-flex align-content-between flex-wrap bd-highlight mb-3" style="height: 200px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex align-content-between flex-wrap">...</div>
{% endhighlight %}
<div class="bd-example">
<div class="d-flex align-content-around flex-wrap bd-highlight mb-3" style="height: 200px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex align-content-around flex-wrap">...</div>
{% endhighlight %}
<div class="bd-example">
<div class="d-flex align-content-stretch flex-wrap bd-highlight mb-3" style="height: 200px">
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
<div class="p-2 bd-highlight">Flex item</div>
</div>
</div>
{% highlight html %}
<div class="d-flex align-content-stretch flex-wrap">...</div>
{% endhighlight %}
Responsive variations also exist for `align-content`.
{% for bp in site.data.breakpoints %}
- `.align-content{{ bp.abbr }}-start`
- `.align-content{{ bp.abbr }}-end`
- `.align-content{{ bp.abbr }}-center`
- `.align-content{{ bp.abbr }}-around`
- `.align-content{{ bp.abbr }}-stretch`{% endfor %}