∞ 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 motionclickmobile-ready

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1

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)
  • demo-v1 preview lifecycle: initialize demoEnabled from window.__foreverPreview and stop attract work on the window forever:interactive event; retain manual feedback, settling, cleanup and explicit sessions

Known limitations

  • First deliberate input permanently disables idle demo; manual input, finite feedback and settling remain active. Host demoEnabled=false skips the initial attract cycle.
  • Border color interpolation uses hardcoded hex constants; changing target requires editing the lerp block
  • State remains local to each mounted instance; format/theme remount preserves takeover, not component values.

formerrorshakemicrointeractionvalidationfeedbackinput

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