Atlas · DS179 · Interaction pattern: Motion

Scroll-Triggered Animation

Elements appear or transform with the scroll position.

Status in 2026: Active. In current use.
Trend 2027 to 2030: Steady (an editorial projection, not a forecast).
The term: Known technical term or standard.

Definition

Elements appear or transform with the scroll position.

Traits

reveal
transitions

Typical settings: Landing pages, editorial.

When to use it, and when not

Consider it when the task and motivation match: visitors exploring promotional content. Typical settings: landing pages, editorial.

Be careful when the risk below would hurt the main task: delays access and distracts.

The audience is a hypothesis

"Visitors exploring promotional content" describes a motivation, task or context for which this direction tends to be chosen. It was not measured, and it says nothing about any age, gender or other group.

UX risk and how to reduce it

Risk: Delays access and distracts.

Mitigation and accessibility: Content accessible without animation.

How to check: Test a prototype against a plain baseline on a real task: completion, time, errors, comprehension, accessibility and preference, segmented by context rather than by stereotype.

Evidence

Indirect: the sources support underlying principles, not a preference for this style.

The sources below support the principles that apply to this term. None of them shows that this style works better or is preferred.

W3C Web Accessibility Initiative 2023 (Standard or guideline): Motion and vestibular disorders.
W3C Web Accessibility Initiative 2021 (Standard or guideline): Cognitive accessibility guidance.

Heuristic scales

Relative editorial judgements from 1 to 5. They are not results of a study and not a measure of quality.

Visual complexity heuristic: 3 / 5 (1 is few visual elements, 5 is many layered elements)
Expressiveness heuristic: 4 / 5 (1 is restrained, neutral, 5 is highly expressive)
Information density heuristic: 2 / 5 (1 is sparse, 5 is dense)

In our library

No design-style recipe in @codeatlasdev/ui implements this term yet. You can still build it from the --ca-* tokens: see Theming.

Prompt for your AI

Paste this into a coding agent. It carries the trade-offs, and asks for a baseline to compare against.

Design this interface in the "Scroll-Triggered Animation" direction (interaction pattern, motion): Elements appear or transform with the scroll position.
Visual and interaction traits to use: reveal, transitions.
Main UX risk: Delays access and distracts. Mitigate it: Content accessible without animation.
Keep it accessible to WCAG 2.2 AA: contrast, visible focus, keyboard operation, 24 px minimum targets, reflow at 320 CSS px and reduced motion.
Keep the content, hierarchy and behavior the same as a plain baseline so the two can be compared. Do not claim the style performs better; the choice should be validated with users.

Limits

The atlas is a broad, living catalogue, not every style that exists. No authority enumerates them, and the classes (movement, aesthetic, design system, layout, pattern, principle) overlap.
The 1 to 5 scores are relative editorial judgements. They are not results of a study and not a measure of quality.
An audience is a hypothesis about motivation, task and context. It was never measured and says nothing about any age, gender or other group.
The sources support underlying principles (visual complexity, legibility, grouping, accessibility, platform conventions). None shows that a particular style works better or is preferred.
The 2027 to 2030 trend is an editorial projection, not a forecast.
Terms in the Future / AI category rest on exploratory work, some of it preprints, with no causal validation.

Last reviewed 2026-10-25.

References

W3C Web Accessibility Initiative (2023). Understanding Success Criterion 2.3.3: Animation from Interactions. W3C WAI, WCAG 2.2 Understanding (Level AAA).Standard or guideline
Supports: Non-essential motion triggered by interaction, such as parallax scrolling, can trigger vestibular disorders (dizziness, nausea, headaches); content should let users turn it off. The criterion is Level AAA.
Does not support: A prevalence figure, or that all animation is harmful. Essential motion is excepted, and the criterion is above the AA level most programs target.
Checked 2026-10-25.
W3C Web Accessibility Initiative (2021). WCAG 2 supplemental guidance. W3C WAI.Standard or guideline
Supports: W3C WAI lists supplemental guidance for improving accessibility beyond what WCAG 2 requires, including a cognitive accessibility guidance set.
Does not support: Normative requirements: supplemental guidance is advisory, not required for conformance. This page is an index; a specific recommendation needs the linked document.
Checked 2026-10-25.