CSS align-content

The CSS align-content property controls alignment of a box's content along the cross/block axis within its content box.

The alignment is similar to how justify-content aligns individual items, however, align-content aligns the whole line. It aligns flex lines within a multi-line flex container when there is extra space in the cross-axis, and aligns grid tracks within a grid container.

To create a multi-line flex container apply flex-wrap with a value of either wrap or wrap-reverse.

Syntax

Possible Values

normal

The default value. Behaves as stretch in flex containers, and start in grid and block containers.

flex-start

Flex items are packed toward the start of the line.

flex-end

Flex items are packed toward the end of the line.

center

Items are packed toward the center of the alignment container.

space-between

Items are evenly distributed in the alignment container. The first item is flush with the start edge, and the last item is flush with the end edge.

space-around

Same as space-between, but with half-size spaces on either end.

space-evenly

Items are evenly distributed so that the spacing between any two items (and the space to the edges) is equal.

stretch

Lines stretch to take up the remaining space. If the leftover free-space is negative, this value is identical to flex-start. Otherwise, the free-space is split equally between all of the lines, increasing their cross size.

start

Items are packed toward the start edge of the alignment container.

end

Items are packed toward the end edge of the alignment container.

In addition, all CSS properties also accept the following CSS-wide keyword values as the sole component of their property value:

initial

Represents the value specified as the property's initial value.

inherit

Represents the computed value of the property on the element's parent.

unset

This value acts as either inherit or initial, depending on whether the property is inherited or not. In other words, it sets all properties to their parent value if they are inheritable or to their initial value if not inheritable.

Basic Property Information

Example Code

Basic CSS

Working Example within an HTML Document

About Flexbox

Flexbox refers to the Flexible Box Layout module introduced in CSS3. Flex items are placed within a flex container. A flex container is an element with either display: flex or display: inline-flex.

In the flex layout model, the children of a flex container can be laid out in any direction, and can "flex" their sizes, either growing to fill unused space or shrinking to avoid overflowing the parent.

For more information on flex items, see the flex property.

CSS Specifications

• The align-content property is defined in CSS Box Alignment Module Level 3 (W3C Working Draft).
• It was originally defined in the CSS Flexible Box Layout Module Level 1 (W3C Candidate Recommendation).

Browser Support

Browser support for CSS properties can vary, particularly for newer or experimental features. Check current browser compatibility before using a property in production, especially when supporting older browsers.

The following table provided by Caniuse.com shows the level of browser support for this feature.

Initial Value

CSS properties have an initial value that applies when the property has not been explicitly set. The initial value is different from the value inherited from a parent element and may vary between properties.

Inheritance

Some CSS properties inherit their computed value from their parent element by default, while others do not. The inherit, initial, unset, and revert keywords can also be used to control how a property gets its value.

Vendor Prefixes

Most modern CSS properties use the standard, unprefixed syntax. Vendor-prefixed properties such as -webkit- are mainly relevant to older browser versions or specific features and should only be used when required by your browser support targets.