/transitions-dev

name: transitions-dev
description: Production-ready CSS transitions for web apps. Use when implementing notification badges, dropdowns, modals, panel reveals, page transitions, card resizes, number pop-ins, text swaps, icon swaps, success checks, avatar group hovers, error state shakes, search/input clear, skeleton loaders, shimmer text, sliding tabs, tooltips, staggered text reveals, card hover tilt, plus-to-menu morph, or accordions. Triggers on "add a transition", "animate the dropdown", "make the modal open smoothly", "swap icon", "page slide", "stagger animation", "open / close transition", "make it animate", "fade between", "success animation", "form error", "shake on invalid", "hover lift", "avatar stack hover", "clear the search", "skeleton loader", "loading shimmer", "shimmer text", "sliding tabs", "segmented control", "tooltip", "reveal text", "tilt card", "3D hover tilt", "cursor glare", "plus to menu", "FAB morph", "accordion", "collapsible", "expand / collapse", "disclosure". Also "motion tokens", "scan for ad-hoc transitions", "replace hardcoded durations with motion tokens", "tokenize my animations", and the commands transitions reveal, transitions review, transitions apply, transitions refine.

Transitions.dev

Twenty-one portable CSS transitions, each namespaced under `t-*` selectors with semantic CSS custom properties. Drop-in: paste the snippet, wire the documented HTML hooks, done. No framework dependencies, no demo-specific markup, and every snippet ships a `prefers-reduced-motion` guard.

Quick reference

| Transition | When to use | Reference | | --- | --- | --- | | **Card resize** | Tween a container's width or height when its layout state changes. | [01-card-resize.md](./01-card-resize.md) | | **Number pop-in** | Re-enter each digit with a blurred slide when a number updates. | [02-number-pop-in.md](./02-number-pop-in.md) | | **Notification badge** | Slide a small badge onto a trigger and pop the dot. | [03-notification-badge.md](./03-notification-badge.md) | | **Text states swap** | Swap text in place with a blurred up-and-down transition. | [04-text-states-swap.md](./04-text-states-swap.md) | | **Menu dropdown** | Open an origin-aware dropdown that grows from its trigger. | [05-menu-dropdown.md](./05-menu-dropdown.md) | | **Modal open / close** | Scale-up modal dialog with a softer scale-down on close. | [06-modal.md](./06-modal.md) | | **Panel reveal** | Slide a panel into a region with a cross-blur. | [07-panel-reveal.md](./07-panel-reveal.md) | | **Page side-by-side** | Slide between two side-by-side pages (list ↔ detail, step 1 ↔ step 2). | [08-page-side-by-side.md](./08-page-side-by-side.md) | | **Icon swap** | Cross-fade two icons in the same slot with blur and scale. | [09-icon-swap.md](./09-icon-swap.md) | | **Success check** | Compose fade + rotate + Y-bob + path stroke-draw to celebrate a completed action. | [10-success-check.md](./10-success-check.md) | | **Avatar group hover** | Distance-falloff lift on a row of items with a bouncy spring on return. | [11-avatar-group-hover.md](./11-avatar-group-hover.md) | | **Error state shake** | Per-segment cubic-bezier shake with auto-reverting border + message. | [12-error-state-shake.md](./12-error-state-shake.md) | | **Input clear with dissolve** | Fly-out + per-word streak when a text field is cleared. | [13-input-clear-dissolve.md](./13-input-clear-dissolve.md) | | **Skeleton loader and reveal** | Pulse a placeholder, then cross-fade + cross-blur to the loaded content. | [14-skeleton-reveal.md](./14-skeleton-reveal.md) | | **Shimmer text** | Sweep a highlight band across muted text on a loop (pure CSS). | [15-shimmer-text.md](./15-shimmer-text.md) | | **Tabs sliding** | Slide the active pill between tabs in a segmented control. | [16-tabs-sliding.md](./16-tabs-sliding.md) | | **Tooltip open/close** | Delayed fade+scale in, instant out (pure CSS). | [17-tooltip.md](./17-tooltip.md) | | **Texts reveal** | Staggered blurred rise for stacked text lines, quiet fade out. | [18-texts-reveal.md](./18-texts-reveal.md) | | **Card hover tilt** | Tilt a card in 3D toward the pointer with a cursor-tracked glare. | [19-card-tilt.md](./19-card-tilt.md) | | **Plus to menu morph** | Morph a circular trigger into the menu / panel it opens. | [20-plus-menu-morph.md](./20-plus-menu-morph.md) | | **Accordion expand** | Grow / shrink a panel via grid-rows with a chevron flip. | [21-accordion.md](./21-accordion.md) | | **Toast open / close** | Rise a toast from below with fade + cross-blur, slower in than out. | [22-toast.md](./22-toast.md) | | **Like button** | Fill a heart with a pop + particle burst on like. | [23-like-button.md](./23-like-button.md) | | **Learn more hover** | Slide the chevron and spread its arms into an arrow on hover. | [24-learn-more-hover.md](./24-learn-more-hover.md) | | **Checkbox check** | Fill the box, then stroke-draw the checkmark. | [25-checkbox-check.md](./25-checkbox-check.md) | | **Spinning counter** | Spin slot-machine digit reels with vertical motion blur. | [26-spinning-counter.md](./26-spinning-counter.md) | | **Toggle** | Travel the switch thumb with a double-bounce overshoot. | [27-toggle.md](./27-toggle.md) |

Decision rules

When the user asks for a transition, match against the visible UI element first, then the verb:

• **Trigger + small dot floating on top** → notification badge.
• **Trigger + surface that grows from it** → dropdown (anchored, origin-aware) or modal (centered, no anchor).
• **Surface that slides into a region of the page** → panel reveal.
• **Two screens, list ↔ detail or step 1 ↔ step 2** → page side-by-side.
• **Element changes width or height** → card resize.
• **Element's text content changes in place** → text states swap.
• **Two icons in the same slot** → icon swap.
• **A number updates** → number pop-in.
• **Confirmation / success / "done" moment** (checkmark, payment processed, file uploaded) → success check.
• **Hovering an item in a horizont