Sticky Action Bar
Keep the primary actions visible when the page is longer than the screen.
What it adds
A bar that pins the save, submit, or apply actions to the viewport once they would otherwise scroll away.
What your agent is told to do
5
What your agent is told to do
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1
Find the long forms and detail pages where the primary action sits below the fold, and pin those actions.
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2
Let the bar sit inline in the normal flow until it is about to leave the viewport, then stick. Reserve its height so nothing shifts at the moment it changes state.
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3
Keep the bar's DOM position fixed in source order so tab order does not change when it sticks. Moving the element on scroll breaks keyboard navigation.
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Mirror the real state of the form in the bar: disabled while invalid, pending while saving, hidden when the user has no permission to act.
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5
Do not stack a sticky action bar on top of an existing sticky header, mobile bottom navigation, or cookie banner. Pick one owner of the bottom edge.
Edge cases it handles
6
Edge cases it handles
6- The bar must respect safe-area insets so it clears the iOS home indicator.
- An on-screen keyboard on mobile will fight a bottom-fixed bar — decide whether it rides above the keyboard or unsticks entirely.
- Page content must gain bottom padding equal to the bar's height, or the last field is unreachable.
- If permissions change mid-session, the bar's actions must update, not go stale.
- On short viewports where the bar would take a third of the screen, fall back to inline actions.
- Validation errors summarised in the bar must link to the offending field, not just say the form is invalid.
Definition of done
7
Definition of done
7- The primary action is reachable at any scroll position on a page longer than the viewport.
- Nothing jumps when the bar transitions between inline and stuck.
- Tab order and accessible labels are identical in both states.
- No content is trapped under the bar, including on notched devices.
- Disabled, pending, and no-permission states in the bar match the form's real state.
- The feature matches the existing design system.
- No existing functionality is broken.
Related features
Beautiful Empty States
Beautiful Empty States
Replace blank screens with useful, contextual empty states.
What it does
Every list, table, and dashboard in your app has a "nothing here yet" state. Most
apps ship a blank rectangle — and it is often the very first thing a new user sees.
An empty state should say what belongs here, why it is empty, and what to do next.
How it works
- 1 Inventory the empty cases first. List every collection view in the app and
- 2 Distinguish the three kinds of empty. They are not the same, and must not
- 3 Build one reusable empty-state component from the existing design system,
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/beautiful-empty-states
Opening Hours Display
Opening Hours Display
Say whether you are open right now and when you next open.
What it does
A live open or closed state alongside the weekly hours, with holiday closures folded in.
How it works
- 1 Lead with the current state in plain words and follow it with the next transition: open until a time, or closed until a day and time. The weekly table is supporting detail, not the headline.
- 2 Store hours as intervals against the business's own zone, and keep holiday and one-off closures as overrides that win over the regular week rather than as edits to it.
- 3 Compute the state on the server for the first render so the page does not briefly claim the wrong thing, then let the page update itself as the clock crosses a boundary without a reload.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/opening-hours-display
Dark Mode
Dark Mode
Add a dark theme that respects the system preference and the user's choice.
What it does
A complete dark theme, defaulting to the operating system preference and overridable by the user.
How it works
- 1 Audit every colour in the app first and report where they are defined. If colours are hardcoded throughout, extract them into tokens before anything else — that refactor is the bulk of this work.
- 2 Define a dark palette against those tokens. Do not simply invert the light theme.
- 3 Default to the system preference via prefers-color-scheme, and let the user override it.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/dark-mode
How it works
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1
Copy the link
Grab the Markdown instruction URL for this feature.
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2
Give it to your AI
Paste it into Claude Code, Cursor, v0, Lovable — whatever you build with.
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3
It inspects, then implements
Your agent reads your existing app first, then adds the feature to fit it.
Works with your stack
These instructions are written to adapt. They tell the agent to detect your framework, match your existing design system, and reuse what you already have — rather than assuming a particular stack.
Need it tighter than that? Customize the feature and tell it exactly what you're running.