line-up

When To Use

Use this pattern when you need to keep card footer actions aligned at the bottom.

HTML

<article class="line_up" aria-labelledby="line-up-title">
    <section class="line_up_body"><h2 id="line-up-title">Implementation proposal</h2><p>Variable-length summary copy sits above the aligned action row.</p></section>
    <footer class="line_up_footer"><button>Review proposal</button></footer>
</article>

CSS

.line_up {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.line_up_body {
    min-block-size: 0;
}

.line_up_footer {
    margin-block-start: auto;
}

Core Properties

• display, flex-direction, gap, min-block-size, margin-block-start define the spatial behavior for this pattern.

Properties That Break The Layout If Removed

• Removing display, flex-direction, gap, min-block-size, margin-block-start changes the pattern from its documented layout responsibility back toward ordinary flow or an unsafe fixed arrangement.

Constraints And Change Points

• fluid responsiveness is part of the contract; change sizing values only when the new minimum, maximum, or wrap point is documented with the pattern.
• Keep the HTML class hooks and CSS selectors in one-to-one agreement.

Scroll Ownership

No internal scroll container.

Accessibility And Source Order Notes

• Semantic role expectation: Preserve the HTML sample's landmark, list, navigation, form, figure, or article roles; layout classes must not replace semantic elements.
• DOM order expectation: Keep semantic elements, DOM order, reading order, and focus order independent from the visual placement created by the layout classes.
• Focus risk: Any interactive descendants follow DOM order; do not use this pattern to create a visual order that keyboard focus cannot follow.
• Scroll expectation: No internal scroll container.
• Cognitive risk: Low: the pattern should preserve ordinary reading flow when semantic order is already correct.

Browser And Fallback Notes

The CSS uses modern grid, flex, intrinsic sizing, logical properties, or positioning. If a target browser cannot support a property, fall back to ordinary block flow before adding decorative or script-driven layout behavior.

Composition Notes

Use line_up as the stable pattern root and compose additional layout behavior outside that root unless the child class is part of the documented relationship.

Anti-patterns

• Do not add color, border, shadow, typography, or animation rules to reusable pattern CSS.
• Do not use this pattern to repair unclear HTML structure; make the DOM roles legible first.

IA Navigation

Parent: Stacking patterns in Pattern Categories. Next: Layout Recipes for screen-level composition, or return to the Layout Pattern Catalog when choosing another primitive.