Prevent a flex item's height from expanding to match other flex items

html

responsive-design

css

flexbox

byAlex Kataev·Oct 26, 2024

Restrain a flex item's height expansion with the align-self: flex-start; command. This ensures the item retains its individual height, instead of stretching along with the flex container's other children.

.flex-item { align-self: flex-start; }

Implement this within your flex container:

<div style="display: flex;">
  <div class="flex-item" style="height: auto;">I won't stretch!</div>
  <div style="height: 100px;">I'm taller than my sibling</div>
</div>

Simply copy and adapt this code to adjust the specific item's class in your flex container.

Deciphering heights and flexbox

To effectively maintain natural height for flex items within a container, it's beneficial to comprehend the following techniques and considerations:

Rule the heights with `flex` property

The flex attribute enables you to control item sizes flexibly. flex: 1 allows the item to grow based on its content, rather than trying to match the height of adjacent items. Remember, in CSS shorthand, flex: 1 translates to flex: 1 1 0%.

Overriding heights

When precision matters, set a specific height like height: 200px to an element. This counteracts the usual equal-height behavior that is predominant in flex containers.

Wise use of `height: 0%`

height: 0% can help prevent height inheritance when a flex container does not have an explicit height. But when there exists a predetermined container height, prefer align-self.

Employ `max-content` for natural sizing

max-content ensures the maximum width that the content would fill without wrapping. It aids in maintaining the item's natural height, contributing to a responsive and dynamic layout.

Clever separators: margins and borders

Both, margins and borders serve utility in flexbox layouts. Margins offer necessary separation within the container, while borders provide visual contrast, enhancing aesthetics and readability.

CSS compatibility is crucial

Before deploying, ensure to check the compatibility of CSS flexbox properties across various platforms. Websites like Can I use, are useful for these checks.

A pool of alignment options

Test other alingment options like align-self: center for centered vertical alignment, or align-self: baseline to align text baselines across items, enhancing typographic consistency.

Digging deeper: handling complex flex layouts

Looking into `flex-direction`

The flex-direction: column approach, in combination with align-items: start, prevents vertical stretching within the flex container when needed.

Exploring framework solutions

Frameworks like Bootstrap offer quick solutions using prebuilt classes. d-flex and align-items-start can help counteract height syncing, without necessitating customized CSS.