# OTP advance Subtle web animation sketch from [https://mighil.com/animations](https://mighil.com/animations). - **Live demo:** https://mighil.com/animations/otp-advance - **Standalone HTML:** https://mighil.com/animations/otp-advance?download=1 - **This file:** https://mighil.com/animations/otp-advance/otp-advance.md - **Technique:** `verify` ## What it does Digits pop in and focus moves. Paste fills everything. ## Instructions for AI / coding agents Implement this micro-interaction in the user's stack (vanilla HTML, React, Vue, Svelte, etc.). 1. Use the **HTML** as the DOM structure (adapt JSX/templates as needed; keep class names and ids). 2. Include the **Theme** CSS (or map the same variables into the host design system). It switches light/dark with `prefers-color-scheme`. 3. Apply the **CSS** as-is when possible. It uses `var(--text-color)`, `var(--heading-color)`, `var(--background-color)`, etc. from the theme so both modes work. 4. Run the **JavaScript** after the markup mounts. Prefer `DOMContentLoaded` or a framework `useEffect` / `onMount`. 5. Keep motion respectful of `prefers-reduced-motion` if the snippet already checks it. 6. Do not depend on mighil.com runtime or fonts. Theme variables are enough for color. 7. If porting to a component, expose the interactive root via a ref and preserve accessibility attributes (`aria-*`, `role`, `button` types). ## Theme (auto light / dark) ```css /* Auto light / dark — follows prefers-color-scheme */ :root{ color-scheme: light dark; --text-color: hsl(0, 0%, 18%); --heading-color: hsl(0, 0%, 18%); --background-color: hsl(0, 0%, 99%); --bg-color: hsl(0, 0%, 99%); --link-color: hsl(0, 0%, 18%); --visited-color: hsl(0, 0%, 18%); --blockquote-color: hsl(0, 0%, 18%); --code-bg-color: hsl(0, 0%, 95%); --code-color: hsl(0, 0%, 18%); --sub-color: hsl(0, 0%, 29%); } @media (prefers-color-scheme: dark){ :root{ --text-color: hsl(35, 25%, 85%); --heading-color: hsl(35.2, 32.6%, 82.5%); --background-color: hsl(60, 2.2%, 8.8%); --bg-color: hsl(60, 2.2%, 8.8%); --link-color: hsl(34.7, 55.3%, 79.8%); --visited-color: hsla(34.7, 55.3%, 79.8%, 0.85); --blockquote-color: hsl(35, 30%, 75%); --code-bg-color: hsl(30, 5%, 7.8%); --code-color: limegreen; --sub-color: hsla(34.7, 24.7%, 84.9%, 0.78); } } ``` ## HTML ```html
``` ## CSS ```css @keyframes otp-pop{0%,100%{transform:scale(1)}40%{transform:scale(1.08)}} .otp{display:flex;gap:8px} .otp input{ width:42px;height:48px;text-align:center;border-radius:8px;box-sizing:border-box; font:inherit;font-size:1.15rem;font-weight:500;font-variant-numeric:tabular-nums;color:inherit;outline:none; border:1px solid color-mix(in srgb,var(--text-color) 14%,transparent);background:transparent; transition:border-color .2s ease,transform .2s cubic-bezier(.34,1.4,.64,1),background .2s ease; } .otp input:focus{border-color:color-mix(in srgb,var(--text-color) 45%,transparent);transform:scale(1.04)} .otp input.is-filled{background:color-mix(in srgb,var(--text-color) 5%,transparent)} .otp input.is-pop{animation:otp-pop .28s ease-out} @media (prefers-reduced-motion: reduce){ .breath-dot,.breath-ring,.wave.is-live span,.ink-drop, .marquee-track, .skel-line,.save-btn.is-loading .spin,.badge.is-bump,.like-btn.is-pop,.save-status.is-saving .dot,.stars button.is-pop svg, .field.is-invalid input,.save-btn.is-done .check path,.ux-check[aria-checked="true"] .ux-box path,.char-meta.is-warn,.success-banner.is-on path, .typing span,.conn-dot,.indet > i,.toast.is-on .toast-timer > i,.stagger-list.is-in .stagger-item,.submit-wrap.is-loading .submit-ring rect,.submit-wrap.is-settle,.hold-btn.is-settle,.confirm-btn.is-settle,.sync-btn.is-settle,.invite-btn.is-settle,.retry-btn.is-shake-err,.retry-btn.is-shake-ok,.cart-badge.is-pop,.mute-btn .x-line,.presence.is-ping .presence-dot::after,.tag-chip,.nudge-field.is-nudge,.tilt-scene:hover .tilt-tile::before,.demo-replay.is-tap,.hit.is-tap,.stack-toggle.is-tap,.nudge-btn.is-tap,.wipe.is-tap,.save-btn.is-tap,.copy-btn.is-tap,.like-btn.is-tap,.pin-btn.is-tap,.retry-btn.is-tap,.wizard-nav button.is-tap,.mute-btn.is-tap, .scan:hover::after,.scan.is-on::after,.cascade.is-in b,.stepper-val.is-bump,.otp input.is-pop,.rel-time.is-live .rel-dot,.sync-btn.is-spin .sync-arrows,.ok-field.is-ok .ok-check path,.unread-row.is-read .unread-check path,.mic-btn.is-on::before,.mic-btn.is-on::after,.ghost-wrap.is-flash,.cmd-palette li.is-run,.flag-row.is-warn,.mention.is-flash b{animation:none!important} .grow-link::after,.wipe,.wipe .b,.shuffle .card,.odo-digit > b,.flap-reel,.step-node,.step-line > i, .switch,.switch::after,.copy-btn .c-idle,.copy-btn .c-done,.field label,.tip-bubble,.chip,.like-btn svg, .disc-btn svg,.disc-panel,.snack,.save-btn,.ux-box,.seg-pill,.soft-tabs-ink,.list-actions,.success-banner,.search-clear,.pin-btn svg,.submit-ring rect, .hold-btn .hold-fill,.toast,.menu-btn .menu-line,.stars button,.conn,.retry-btn,.sort-item,.mute-btn .wave,.mute-btn .x-line,.wizard-dots span,.cart-badge,.range-bubble, .filter-list li,.upload-bar > i,.quota-track > i,.quota-tip,.splitbtn-toggle svg,.splitbtn-menu,.presence-dot, .draft-banner,.tag-chip,.empty-state,.empty-item,.deadline,.deadline-clock,.deadline-track > i,.edge-fade-mask,.dirty-bar,.seen-ticks path,.nudge-field,.stack-card, .blur-line,.xface span,.magnet-chip,.confirm-btn,.confirm-btn span,.offline-banner,.sort-flip-btn svg,.sort-flip-list li,.react-fan,.react-fan button,.sticky-cta, .pw-toggle .pw-eye,.pw-toggle .pw-slash,.otp input,.exp-search,.exp-search input,.ok-field input,.ok-field .ok-check,.unread-dot,.unread-check,.unread-row,.sync-label,.sync-btn .sync-arrows,.sync-btn .sync-check, .inline-edit .ie-title,.inline-edit .ie-rename,.inline-edit .ie-panel,.inline-edit .ie-input,.inline-edit .ie-bar, .ghost-wrap .ghost-hint,.ghost-wrap .ghost-key,.cmd-palette,.cmd-palette li,.cmd-stage::before,.crumb-mid,.crumb-more,.diff-add,.diff-add > .diff-add-inner,.slot > i,.zoom-thumb,.zoom-full,.zoom-caption, .bulk-bar,.bulk-check svg,.bulk-row,.env-switch .env-ink,.env-switch button,.invite-btn .invite-idle,.invite-btn .invite-done,.flag-row,.flag-sw,.flag-sw::after,.deploy-node,.deploy-node i,.deploy-wire > b,.ws-ink,.ws-item .ws-check,.thread,.thread-body,.thread-resolve svg, .unfurl-card,.unfurl-thumb,.seat,.form-prog-bar > i,.form-prog-field,.form-prog-field svg,.mention b,.glyph-tile path,.glyph-tile line,.glyph-tile circle{transition:none!important} } ``` ## JavaScript ```js // OTP advance const otp = document.getElementById('otp'); function resetOtp() { if (!otp) return; [...otp.querySelectorAll('input')].forEach((inp) => { inp.value = ''; inp.classList.remove('is-filled', 'is-pop'); }); otp.querySelector('input')?.focus(); } if (otp) { const inputs = [...otp.querySelectorAll('input')]; inputs.forEach((inp, i) => { inp.addEventListener('input', () => { const v = inp.value.replace(/\D/g, '').slice(-1); inp.value = v; inp.classList.toggle('is-filled', !!v); if (v) { inp.classList.remove('is-pop'); void inp.offsetWidth; if (!reduce) inp.classList.add('is-pop'); if (i < inputs.length - 1) inputs[i + 1].focus(); } }); inp.addEventListener('keydown', (e) => { if (e.key === 'Backspace' && !inp.value && i > 0) { inputs[i - 1].focus(); inputs[i - 1].value = ''; inputs[i - 1].classList.remove('is-filled'); } }); inp.addEventListener('paste', (e) => { e.preventDefault(); const text = (e.clipboardData || window.clipboardData).getData('text').replace(/\D/g, '').slice(0, inputs.length); text.split('').forEach((ch, j) => { inputs[j].value = ch; inputs[j].classList.add('is-filled'); if (!reduce) { inputs[j].classList.remove('is-pop'); void inputs[j].offsetWidth; inputs[j].classList.add('is-pop'); } }); inputs[Math.min(text.length, inputs.length - 1)].focus(); }); }); } document.querySelectorAll('[data-act]').forEach((btn) => { btn.addEventListener('click', (e) => { e.stopPropagation(); const act = btn.getAttribute('data-act'); if (act === 'otp') resetOtp(); }); }); ``` --- _Source: https://mighil.com/animations/otp-advance_