# Pill accordion > Pills that grow into cards over a product photo, on a CSS-only glass material: one open at a time, stepped with Previous and Next. Surfaces · [Docs](https://ui.ssntl.app/docs/components/pill-accordion) · `npx shadcn@latest add @ssntl/pill-accordion` Installs `components/ui/pill-accordion.tsx`, with `utils`, `elevation`. Read this file before you use, change or review it. ## When to use it - To tour the features of one product over its photo or video, one short card at a time. ## When not to - For long answers or several open at once: use Accordion. - Without a photo or video behind it: on a flat surface, use Accordion. ## Usage ```tsx import { PillAccordion, PillAccordionClose, PillAccordionContent, PillAccordionItem, PillAccordionList, PillAccordionNext, PillAccordionPrevious, PillAccordionTrigger, PillAccordionTriggerIcon, } from "@/components/ui/pill-accordion" ; Orders

Orders. From the table to the kitchen.

``` ## Rules for Pill accordion - **One open at a time.** The pill grows into a card while the others make room; focus moves into the card, and Escape or Close returns it to the pill. - Previous and Next step between cards without closing; at the ends they stay focusable (`aria-disabled`) so focus never drops to the page. - The morph animates the item's size over 400ms on `--ease-in-out`; the label leaves at once, and the text arrives only once the card is two-thirds grown, lifting 8px, so it never shows clipped. Reduced motion: the size changes at once and the text only fades. - **Glass.** The glass utility, clear enough to see the photo through and measured at 4.5:1 or more with pure black or white behind it, in both themes; with reduced transparency it turns solid. - **Hit areas.** Pills are 56px tall; the round buttons are 40px discs inside a 48px target. - Name the buttons for what they step through (“Next feature”), and keep each card to a sentence or two. - Drive a photo beside it with value and `onValueChange`; cross-fade with opacity, keeping every photo mounted. ## Keyboard | Key | Action | | ------------- | ----------------------------------------------------------------------------- | | Tab | Moves through the pills; with a card open, to its text and the round buttons. | | Enter / Space | On a pill: opens its card and moves focus into it. | | Escape | Closes the card and returns focus to its pill. | ## How it is built An accordion of pills, for touring the features of a product over its photo: the pill you choose grows into a card while the others make room. Adapted from Chánh Đại's Apple Accordion (MIT, chanhdai.com), rebuilt on the system's tokens and glass material, with no UI library underneath. - One open at a time. Focus moves into the card as it opens; Escape or Close shrinks it back and returns focus to its pill. - Previous and Next step between cards without closing; at either end they stay focusable (aria-disabled), so focus never drops to the page. - The morph: both the pill and the card stay laid out, measured, and the item animates between their sizes over 400ms on --ease-in-out. Opening, the label leaves at once and the text comes into focus (blur and fade, no travel) once the card has room. Closing, the text leaves first, then the card shrinks, then the label returns. Under reduced motion the size changes at once and the text only fades. - Hit areas: pills are 56px tall, the round buttons 40px inside a 48px target. The pill turns inert and the card stops being inert in the same commit, so moving focus right after can't miss. The step buttons keep focus, so pressing again keeps stepping. Names the set: “Features of the studio plan”. The step buttons need the order before anything opens, and only the list sees every item. Until measured, the pill in flow sizes the item by itself. The size morphs on screen (in-out); hover is quick (out). The card covers it while open, so it leaves the tab order too. Leaves at once; returns once the card has nearly shrunk back. Sized by its own text, never wider than the room beside the buttons. Comes into focus once the card is two-thirds grown: a 4px blur that clears with the fade, no travel. On close it leaves in 100ms, before the card starts to shrink, so it is never clipped. Reduced motion keeps the fade only. The step and close buttons: a 40px glass disc inside a 48px target, shown only while a card is open. aria-disabled, not disabled: a disabled button would drop focus to the page when stepping reaches the end. ## API notes - `value`: The open item's value, or null when every item is a pill. - `defaultValue`: The item open on mount, when uncontrolled. - `value`: A unique value for the item. - `PillAccordionTriggerIcon`: The round plus at the start of a pill; pass another icon as children. ## Motion - Animate only to explain a change; the interface is complete without motion. - **Durations from tokens.** `--duration-fast` 150 (press, hover), `--duration-pop` 180 (tooltips, icon swaps), `--duration-menu` 220 (menus, small moves), `--duration-panel` 320 (modals, sheets). - **Easing from tokens.** `--ease-out` for entrances, exits and presses; `--ease-in-out` for things already on screen moving to a new place; linear for progress only. - Use transitions for interactions so they can be interrupted; keyframes only for one-off sequences. - Name the properties you transition (transition-[scale,opacity]); never transition: all. - **Don't animate on page load.** Content that is already there appears at once; entrance motion is for things that arrive later. - No custom animation on high-frequency interactions (typing, toggling in a list, hovering a table, keyboard shortcuts, a command palette); the cost repeats every time. - Never `ease-in` on interface motion: it starts slow, exactly when the person is watching. - **Never animate from scale(0).** Start at 0.9–0.97 with opacity 0 (`pop-in` starts at 0.96). The one exception is a cross-fading icon (`icon-swap`), which starts at 0.25 behind a blur. - Popovers and menus grow from their trigger (transform-origin at the trigger); modals stay centered. - Keep animated blur under 20px; a 2–4px blur masks an imperfect cross-fade. - `will-change` only once you see first-frame stutter, naming the property that animates (scale, not transform), and never on an element that doesn't animate; it also makes the element the container of fixed descendants. - Entrances stagger 100ms apart (80ms per word in a headline): each chunk rises 12px out of a 4px blur over `--duration-panel`, and exits travel less, faster. - Icon cross-fades run on `--duration-pop` with cubic-bezier(0.2, 0, 0, 1), and only for infrequent swaps; a tab's icon or an action revealed on hover swaps instantly. (better-ui suggests 300ms; the system keeps its 180ms token, under the 300ms limit for interface motion.) - Exits are quicker and travel less than entrances; animate opacity, translate, scale and filter, never layout properties. - Under reduced motion keep opacity and color only. No state lives in motion alone. ## Interaction - Every control has an accessible name: its visible label, or `aria-label` for icon-only controls. - Every keyboard-reachable control shows a visible focus ring (2px, offset 2px, the ring token). - Anything you can do with a pointer you can do with the keyboard. - Targets are 48px (44px minimum for dense rows), with at least 8px between neighbours (the system's density); the hit area covers the whole visible control. - Press feedback is 0.96 scale in 150ms (`--es-press`, `--duration-fast`); never below 0.96, never slow, and a disabled control never scales. - One primary action per view; past three secondary actions, the rest go in a menu. - Hover styles only on pointer devices; never hide a control's function behind hover. - **Undo beats confirmation.** A frequent, reversible action runs at once and offers Undo (Order archived. Undo). Confirm only what can't be undone, affects other people or destroys many items. A destructive action is red text, placed last. - Never disable a submit button until the form is valid; validate on submit. While pending, use `aria-disabled="true"` with a spinner beside the label, since disabled drops focus. ## Images - Decorative images take `alt=""`; an image that carries information gets alt text that says what it shows. - Images get a 1px pure black (white in dark) outline at 10%, offset −1px; transparent artwork such as logos and cut-out objects skips it. - Images in a set share one ratio and are cropped to fit; serve twice the displayed size and set width and height. - Never put text on an image without a scrim; never use a brand-bearing asset you don't have rights to. ## Design tokens only - Use the system's tokens for every design value: type roles (`text-caption` 13, `text-label` 15, `text-body` 17, `text-lead` 20, `text-heading` 22, `text-title` 32, `text-headline` 48, `text-display` 72), radii (`rounded-xs` 8 … xl 44), spacing steps, colors, shadows and motion. If a value doesn't exist, take the nearest token. Never write text-[15px], rounded-[24px] or bg-[#…]; `pnpm lint` rejects them. - Type roles already carry line height, tracking and weight. Pick the role; never add `leading-*` or `tracking-*` on top. - **Nested corners are concentric.** Inner radius = outer radius − padding − border width (`rounded-outer`-* p-concentric-* `rounded-inner`). Past 24px of padding, or with deliberately uneven padding, each layer keeps its own radius token. - Separate surfaces by tone, not borders. A border is for structure (a divider) or state (an input, a selection). ## Accessibility baseline - Text meets 4.5:1 against its surface (3:1 at 24px and up, or 18.67px bold); input borders, focus rings and chart marks meet 3:1, in light and dark. Text on a translucent color (`white/80`, /50, color-mix) is measured as rendered over its background; the theme pairs are checked in lint. - Meaning never rides on color alone: a state carries a word, an icon or a pattern as well. - Every page fits a 320px screen at 200% zoom with no horizontal scroll; a grid that holds content uses grid-cols-[minmax(0,1fr)] and flex children get min-w-0. Never set maximum-scale=1 or user-scalable=no. - A focused element is never hidden under sticky chrome: set scroll-padding to the header's height (and to footers or banners at the bottom). - On a client-side route change, update the title and move focus to the new page's main content. - **Respect prefers-reduced-motion.** Keep opacity and color, drop movement, scale and blur. - Content is never truncated without a way to read all of it; long names wrap. A hover-only title tooltip doesn't count as a way back. ## Writing - Sentence case everywhere; no ALL CAPS except the Eyebrow role. - One concept, one word, across navigation, headings and buttons. - Buttons are a verb and its object and say what happens (Delete product, not OK). - An error says what went wrong and how to fix it, in the user's language. - **Status copy follows one pattern.** In progress is the verb in -ing (Saving changes…), done names the object and the past tense with no “successfully” (Changes saved), a failure gives the next step, partial results give counts. Cut “Please”. - A confirmation names the action and the object (Delete Ceramic cup?), never “Are you sure?”. Deleting an account, a workspace or a store asks for its name to be typed. - Show known requirements as helper text before input, not only as an error after it. Links never say “Click here”, and no two links on a page say “Learn more”. - Build each sentence as one translatable message, never concatenated around a variable; join lists with Intl.`ListFormat`. - **Use real characters.** An en dash for ranges (09:30–17:45), × for dimensions, curly quotes, an ellipsis (…). ## Fixing - Take the cheapest fix that works, in this order: delete (a separator space would carry, an animation on a frequent action, an ARIA attribute a native element makes redundant), use the platform (the native element or control, the browser's focus ring), reuse what the system has (a token, a spacing step, a motion curve), correct the value, and only then add something new. - Code that adds what a deletion would fix is a problem in itself; fix it by removing. - A documented convention settles matters of taste, but never excuses a release blocker. ## Worst-case content - Build and test with the worst real values, not the happy ones: long hyphenated names with diacritics, unbreakable emails and URLs, German compounds, translations about 30% longer, emoji and right-to-left names. - Unbreakable strings wrap anywhere; nothing pushes its siblings off a row or out of a container. - Every image has a fallback and a box: a failed avatar shows initials, a frame keeps its ratio, so loading never shifts the layout. - **Show data as data.** Escape HTML, never render null, undefined or NaN, and round floating point before display. - **Check the environment as well.** A 280px column, a 2560px screen, 200% zoom, dark mode, `dir="rtl"` and touch. ## Icons - One icon set (Lucide) at one stroke: 1.6, the Essential Design spec, beside regular and medium text; a heavier stroke only where a small glyph must read (a 16px check). (better-ui proposes rendered strokes of 1.5–2px with `absoluteStrokeWidth`; the system's documented stroke takes precedence as a matter of style.) - Inline icons are 1em–1.25em of the text beside them. - Icons are 20px beside labels and 16px in dense controls, at the size they were drawn; a well or a button, not a bigger glyph, gives them room. - One SVG per icon, colored with `currentColor`; hover, selected and disabled states come from color and opacity, never from separate assets. - Decorative icons are `aria-hidden`; an icon that is the only content of a control gets its name from the control. ## Light, dark and languages - Design both themes from the tokens; dark mode is chosen, not inverted. Check every new pair in both. - Pass every visible and accessible string as a prop or child, so the component works in any language; never hard-code copy inside it. - Use logical properties (ms-, me-, start-, end-) so layouts mirror in right-to-left languages; `translateX` and background-position need a right-to-left override. Mirror only icons whose meaning follows reading direction (arrows, chevrons), and wrap mixed-direction values in ``. - **Visual order matches DOM order.** No order, row-reverse or grid placement that reorders content. - Switching themes pauses transitions for the switch, so every surface changes at once. ## Before you ship - [ ] Every interactive control has an accessible name. - [ ] Every keyboard-reachable control shows a visible focus indicator. - [ ] Nothing is reachable by pointer but not by keyboard. - [ ] Motion and auto-playing content respect prefers-reduced-motion. - [ ] Nothing is clipped, overlapped or unreachable at 320px width or 200% zoom. - [ ] Body and control text pass their contrast ratio. - [ ] No state or meaning is carried by color alone. - [ ] Destructive actions have a confirmation, an undo, or a distinct treatment. - [ ] No content is truncated without a way to reach the full value. - [ ] No content or control hides past a scroll edge or disclosure without a visible cue. - [ ] Every error names a way to recover. - [ ] Semantic colors are used for their meaning only (danger never on a safe action). - [ ] No state change is carried by motion alone. - [ ] Nothing focused hides under sticky chrome, and overlays contain their own scroll. - [ ] Worst-case values (long, empty, many, missing, right-to-left) don't break the layout. ## Review with these skills Every interface built with ssntl/ui is reviewed with the same skills the library is. Install them once and keep them current: ```bash npx skills@latest add https://github.com/jakubkrehel/skills --skill better-interface npx skills@latest add jakubkrehel/make-interfaces-feel-better npx skills@latest add emilkowalski/skills ``` - **better-interface** (Jakub Krehel): The full review: accessibility, layout, writing, typography, color and polish. Its escalation triggers block a release. - **make-interfaces-feel-better** (Jakub Krehel): The details: concentric radii, optical alignment, press scale, interruptible and subtle motion, hit areas. - **emilkowalski/skills** (Emil Kowalski): Design engineering: easing, durations, springs and gestures (emil-design-eng, review-animations, animation-performance) and the worst-case values that break a UI (break-ui). ## Related - [Accordion](accordion.md): Disclosure sections that open first and let their lines follow through. - [Carousel](carousel.md): A looping carousel with neighbours peeking in and a progress dot per card: autoplay pauses on interaction and off screen, and waits for Play with reduced motion. - [Elevation](elevation.md): Five levels built from smooth shadows, from the base surface to modals, the pop-in and pop-out motion for floating layers, and a CSS-only glass material. --- Generated from the ssntl/ui source by `scripts/build-rules.mjs`. The whole rulebook is [ssntl-ui.md](ssntl-ui.md); every component's rules are at https://ui.ssntl.app/rules.