∞ forever components

Feedback & States

Error Shake

Dark email input shakes horizontally with decaying-sine, border flushes red, X icon pops in with overshoot spring, validation message slides up.

cssmedium complexitymoderate motionclick

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When to use it

Form validation feedback, login/signup error states, any input needing a tactile rejection signal.

When not to

High-frequency repeated errors — the 2.7s hold+reset cycle feels sluggish; reduce settle time or debounce triggers.

Working with an AI agent

Every component ships agent-ready metadata. An example instruction for this one:

Change shake amplitude from AMP=13 to AMP=8, set border target color to orange-red by editing the hex constants in the lerp block, and update msg.textContent to "invalid address". Theme: dark tokens live in :root, the light variant in :root[data-theme="light"]; ?theme=light or a {type:'forever:theme'} postMessage switches at runtime.

Safe to edit

  • shake amplitude (AMP=13)
  • decay rate (DECAY=7.5)
  • error message text (msg.textContent)
  • border target color (hex constants in lerp block)
  • auto-cycle interval (nextAuto 3200ms)
  • X mark overshoot scale (0.18)
  • theme tokens (:root dark defaults + [data-theme=light] overrides)

Keep intact

  • IIFE wrapper
  • prefers-reduced-motion guard (applyStatic fallback)
  • visibilitychange pause/resume
  • aria-live polite on #fb02-msg
  • theme hook (?theme= bootstrap + forever:theme message listener + theme tokens)

Known limitations

  • Auto-cycles in demo — remove nextAuto scheduler and call trigger() manually for production
  • Border color interpolation uses hardcoded hex constants; changing target requires editing the lerp block

formerrorshakemicrointeractionvalidationfeedbackinput

More Feedback & States components

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  • Toast StackDark notification toasts spring up from the bottom, drain a colored progress bar, then slide off right. Four types cycle: success, error, warning,…
  • Slide to ConfirmDraggable pill slider fills green on full slide; early release triggers a red shake. Spring physics snap thumb back. Auto-demos with an occasional failure…
  • Hold to ConfirmPress-and-hold fills a tick-marked ring; full hold rotates center square 45° into a green check; early release flashes red cross (cancelled).
  • Empty StateA Bauhaus open vessel sits empty while 26 mint motes drift in a slow orbital cloud above it; poking scatters them and they spring back to settle.
  • Like BurstHeart dips then spring-pops into a magenta-mint gradient, firing a 96-particle synthwave burst of dots and ring shards. Auto-cycles when idle.