Better UI

Details that make interfaces feel better

Great interfaces rarely come from a single thing. It's usually a collection of small details that compound into a great experience. Apply these principles when building or reviewing UI code.

Adapted from Jakub Krehel's better-ui at commit a67333399dabbc71d7778962cb9c4fb9b86a00d0.

When reviewing, slow the interface down: replay motion at 10% speed in the browser's Animations panel and walk every state: hover, focus, active, loading, empty. What feels off at 10% speed is what's subtly wrong at full speed.

Preserve the project's component library, tokens, density, and motion language. Exact values in this skill are fallback recipes only when the project and Studio have no tuned value; they never override either source.

Typography (text wrapping, font rendering, tabular numbers, spacing) is covered by the better-typography skill; use that for anything text-related. Accessibility (hit areas, focus states, keyboard support, ARIA, reduced motion) is covered by the better-accessibility skill. Layout structure (grouping, spacing between sections, breakpoints, spatial RTL) is covered by the better-layout skill.

Quick Reference

Core Principles

1. Concentric Border Radius

Outer radius = inner radius + padding. Mismatched radii on nested elements is the most common thing that makes interfaces feel off.

2. Optical Over Geometric Alignment

When geometric centering looks off, align optically. Buttons with icons, play triangles, and asymmetric icons all need manual adjustment.

3. Shadows for Elevation, Borders for Structure

For buttons, cards, and containers whose border exists only to create depth, prefer layered transparent box-shadow values. Keep borders that communicate structure or state: dividers, layout separators, and selected or focus states.

4. Interruptible Animations

Use CSS transitions for interactive state changes: they can be interrupted mid-animation. Reserve keyframes for staged sequences that run once.

5. Split and Stagger Enter Animations

For an infrequent staged entrance where sequence helps communicate hierarchy, break content into semantic chunks and stagger them by ~100ms instead of animating one container. Do not stagger routine, high-frequency interactions.

6. Subtle Exit Animations

Use a small fixed translateY instead of full height. Exits should be softer than enters. Use the project's exit easing; absent one, tune against Studio's current motion default.

7. Contextual Icon Animations

Animate icons with opacity, scale, and blur instead of toggling visibility. When no project recipe exists, start with scale 0.25 to 1, opacity 0 to 1, and blur 4px to 0px, then tune. If the project has motion or framer-motion, match its established import and transition language. Otherwise keep both icons in the DOM and cross-fade them with CSS transitions.

8. Image Outlines

When images need a consistent edge, use the project's image-outline token. Without one, start with a subtle 1px neutral-black outline in light mode and neutral-white in dark mode at low opacity. Avoid an accidental tinted neutral, which can read as dirt against the image edge.

9. Scale on Press

A subtle press scale gives buttons tactile feedback. Without a project value, start at 0.96; values below 0.95 usually feel exaggerated. Add a static escape when motion would distract.

10. Skip Animation on Page Load

Use initial={false} on AnimatePresence to prevent enter animations on first render. Verify it doesn't break intentional entrance animations.

11. Never Use transition: all

Always specify exact properties: transition-property: scale, opacity. Tailwind's transition-transform covers transform, translate, scale, rotate.

12. Use will-change Sparingly

Only for transform, opacity, filter, the properties the GPU can composite. Never use will-change: all. Only add when you notice first-frame stutter.

13. Match Icon Stroke to Text Weight

An icon next to text carries the text's optical weight. Match the project's icon system; without one, try 1.5px beside regular text and 2px beside semibold text. Keep one coherent icon family and stroke language per surface.

14. One SVG, Recolored per State

Icons use currentColor and get their states (hover, selected, disabled) from CSS color and opacity, never from separate assets. Outline variant is the default; fill variant marks the active state.

15. Motion Restraint

No custom animation on high-frequency interactions: the attention cost repeats on every trigger. Motion is never the only feedback channel; every animated state change also needs a static cue (color, icon, label).

16. Derive Adaptive Chips; Do Not Blend by Default

For neutral chips and badges placed on changing surfaces, inherit the surface foreground with currentColor and derive translucent fills and borders from it. Keep semantic success, warning, error, and status colors on explicit tokens. Treat mix-blend-mode as an art-directed exception for controlled backdrops, not as the component-system default.

Common Mistakes

Review Output Format

Use this format only when the user asks for a standalone UI-polish review. When studio-audit orchestrates the review, provide domain evidence and findings to that skill and let its output format, severity scale, consolidation rules, cap, and verdict take precedence.

Present the standalone review in two parts.

Findings

Group all confirmed findings by principle. Use a markdown table with Severity, Location, Before, After, and Why columns. Never use separate "Before:" / "After:" lines.

• Severity: HIGH makes an interaction misleading, unresponsive, or repeatedly disruptive; MEDIUM creates a noticeable craft or consistency problem; LOW is isolated polish.
• Location: cite path/to/file:line. If the artifact has no source files, cite the exact screen and component instead.
• Before / After: show the current implementation and an actionable replacement.
• Why: name the violated principle and explain how it affects the interface.

Consolidate a repeated systemic issue into one row and list every affected location. Omit principles with no findings.

Example

Concentric border radius

Scale on press

Verification and Verdict

After the findings:

1. Verification: list the exact checks run and their observed results. Walk every relevant state and inspect motion at 10% speed when animation is involved. If a check was not run, state what still needs verification.
2. Verdict: Block if any HIGH finding remains, Needs changes if only MEDIUM or LOW findings remain, and Approve only when no actionable findings remain.

When there are no findings, omit the tables, state "No actionable UI-polish findings", report verification, and end with Approve.