align-content

The align-content property is a sub-property of the Flexible Box Layout module.

It helps to align a flex container’s lines within it when there is extra space in the cross-axis, similar to how justify-content aligns individual items within the main-axis.

Note, this property has no effect when the flexbox has only a single line.

The align-content property accepts 6 different values:

flex-start: lines packed to the start of the container
flex-end: lines packed to the end of the container
center: lines packed to the center of the container
space-between: lines evenly distributed; the first line is at the start of the container while the last one is at the end
space-around: lines evenly distributed with equal space between them
stretch (default): lines stretch to take up the remaining space

The following figure helps understand how the lines are stacked up in a flex container depending on the align-content value:

Syntax

align-content: flex-start | flex-end | center | space-between | space-around | stretch

.flex-container {
  align-content: space-around;
}

Demo

The following demo shows how lines are stacked out depending on the align-content value:

The red list is set to flex-start
The yellow list is set to flex-end
The blue list is set to center
The green list is set to space-between
The pink list is set to space-around
The brown list is set to stretch

Browser support

This is support for Flexbox as a whole, which should be the same as this property, since it’s kind of an original property as it were.

This browser support data is from Caniuse, which has more detail. A number indicates that browser supports the feature at that version and up.

Desktop

Chrome	Firefox	IE	Edge	Safari
21*	28	11	12	6.1*

Mobile / Tablet

Android Chrome	Android Firefox	Android	iOS Safari
123	124	4.4	7.0-7.1*

For more information about how to mix syntaxes in order to get the best browser support, please refer to this article (CSS-Tricks) or this article (DevOpera).