Exclusivebeta

Lifelines — `<mv-lifelines>`

Decision helpers for a hard single choice (a plan, a shipping option, a laptop configuration, an insurance tier, an instance size), each a lifeline with a limited number of uses that is visibly spent. It wraps your own native radios or option cards and never replaces them, so the form value, validation and arrow keys stay the browser's. “Narrow it down” sets aside the options that clearly don't fit the user's stated needs, using your narrow(context) function or data-fit scores. Each removal carries its reason, the current pick is never hidden, a minimum number of options is kept, and “Show them” brings the set-aside options back, still selectable. “What others chose” adds a distribution bar with a percentage to every option, overall and for a “people like you” segment, from data-share attributes or a stats object or function, and marks the most chosen option. “Ask someone” writes an editable message with the shortlist and your current pick, plus an optional vote link, and sends it through the Web Share API or copies it. Answers come back through addVote() and show on each option. A confidence readout combines fit, crowd and votes for the current pick into a Strong / Moderate / Low level with its reasons. Every lifeline goes through a cancelable mv-lifeline event whose waitUntil(promise) can fetch fits, statistics or a poll link from your server.

Category	Forms
Type	Web Component (`<mv-lifelines>`)
Status	beta
Also installs	button, textarea
Keywords	exclusive, culture, decision, choice, radio-group, option-cards, plan-picker, pricing, shipping, configurator, recommendation, social-proof, share, web-share, voting, confidence, filter, form

When to use

Users stall on a plan, tier or configuration picker and need help ruling out options before they commit
The app knows the user's needs (team size, deadline, budget) and can explain why an option doesn't fit
Showing what similar customers picked would reassure a hesitant buyer without pushing a single recommendation
A purchase is often decided with a colleague or partner, and the shortlist should be easy to send them for a vote

Avoid when

The options only need to be listed as cards with a price and badge, with no decision help → use Radio instead
Plans must be compared feature by feature in a full pricing section with a billing toggle → use Pricing instead

Install

node scripts/add.mjs lifelines --out ./src/marvelous

AI agent with the Marvelous UI MCP server: install_components({ slugs: ["lifelines"], target_dir: "<absolute path>/src/marvelous", framework: "react" }).

Files copied (dependencies included): tokens/tokens.css, core/base.css, core/dom.js, core/element.js, core/motion.js, components/lifelines/lifelines.js, components/lifelines/lifelines.css, components/button/button.css, components/textarea/textarea.css, components/textarea/char-count.js.

Usage

Canonical markup — start from it and customize with attributes, data-* and CSS variables:

<div id="ll-demo" style="width:min(100%,66rem);margin-inline:auto">
  <style>
    #ll-demo { display:grid; gap:1.25rem; align-content:start }
    #ll-demo .ll-layout { display:grid; grid-template-columns:minmax(0,1fr) 16.5rem; gap:1.25rem; align-items:start }
    #ll-demo .ll-card { min-width:0; border:1px solid var(--mv-border); border-radius:var(--mv-radius-xl); background:var(--mv-surface); box-shadow:var(--mv-shadow-sm) }
    #ll-demo .ll-head { display:flex; align-items:flex-end; justify-content:space-between; gap:.75rem 1.25rem; flex-wrap:wrap; padding:1.125rem 1.25rem 1rem; border-bottom:1px solid var(--mv-border) }
    #ll-demo .ll-head h3 { margin:0; font-size:1.0625rem; letter-spacing:-.01em }
    #ll-demo .ll-head p { margin:.1875rem 0 0; color:var(--mv-fg-muted); font-size:.8125rem }
    #ll-demo .ll-needs { display:flex; align-items:flex-end; gap:.75rem; flex-wrap:wrap }
    #ll-demo .ll-need { display:grid; gap:.3125rem; font-size:.75rem; font-weight:500; color:var(--mv-fg-muted) }
    #ll-demo .ll-need .mv-select { width:auto; min-width:7.5rem; height:var(--mv-control-sm); font-size:.8125rem }
    #ll-demo .ll-need .mv-choice { height:var(--mv-control-sm); align-items:center; font-size:.8125rem }
    #ll-demo .ll-body { padding:1.125rem 1.25rem 1.25rem }
    #ll-demo .mv-choice-group legend { font-size:.8125rem; color:var(--mv-fg-muted) }
    #ll-demo .mv-radio-meta { margin-inline-start:auto; padding-inline-start:.5rem; font-weight:600; font-size:.875rem; white-space:nowrap; font-variant-numeric:tabular-nums }
    #ll-demo .mv-radio-meta small { color:var(--mv-fg-muted); font-weight:500; font-size:.75rem }
    #ll-demo .ll-side { position:sticky; top:1rem; display:grid; gap:1rem; padding:1.125rem; border:1px solid var(--mv-border); border-radius:var(--mv-radius-xl); background:var(--mv-surface-raised); box-shadow:var(--mv-shadow-sm); font-size:.8125rem }
    #ll-demo .ll-side h4 { display:flex; align-items:center; justify-content:space-between; gap:.5rem; margin:0; font-size:.8125rem; font-weight:600 }
    #ll-demo .ll-side p { margin:0; color:var(--mv-fg-muted); font-size:.75rem; line-height:1.45 }
    #ll-demo .ll-votes { display:grid; gap:.5rem }
    #ll-demo .ll-votes .mv-button { justify-content:flex-start; width:100% }
    #ll-demo .ll-sep { height:1px; background:var(--mv-border) }
    #ll-demo .ll-log { display:grid; gap:.3125rem; margin:0; padding:0; list-style:none; font:.6875rem/1.45 var(--mv-font-mono); color:var(--mv-fg-muted) }
    #ll-demo .ll-log li { overflow:hidden; text-overflow:ellipsis; white-space:nowrap }
    #ll-demo .ll-log b { color:var(--mv-fg); font-weight:500 }
    #ll-demo .ll-ship .ll-body { display:grid; grid-template-columns:minmax(0,15rem) minmax(0,1fr); gap:1.5rem; align-items:start }
    #ll-demo .ll-order { display:grid; gap:.625rem; font-size:.8125rem }
    #ll-demo .ll-order dl { display:grid; gap:.375rem; margin:0 }
    #ll-demo .ll-order dl div { display:flex; justify-content:space-between; gap:.5rem }
    #ll-demo .ll-order dt { color:var(--mv-fg-muted) }
    #ll-demo .ll-order dd { margin:0; font-variant-numeric:tabular-nums }
    #ll-demo .ll-order .ll-by { display:flex; gap:.5rem; align-items:flex-start; padding:.625rem .75rem; border-radius:var(--mv-radius-lg); background:var(--mv-bg-subtle); color:var(--mv-fg-muted); font-size:.75rem; line-height:1.45 }
    #ll-demo .ll-order .ll-by b { color:var(--mv-fg); font-weight:600 }
    #ll-demo .ll-hint { margin:0; color:var(--mv-fg-muted); font-size:.75rem; text-align:center }
    @media (max-width:54rem) {
      #ll-demo .ll-layout { grid-template-columns:minmax(0,1fr) }
      #ll-demo .ll-side { position:static }
      #ll-demo .ll-ship .ll-body { grid-template-columns:minmax(0,1fr) }
    }
  </style>

  <div class="ll-layout">
    <!-- Main: choosing a workspace plan, with the app's own narrow() and stats() -->
    <section class="ll-card" aria-labelledby="ll-plan-title">
      <header class="ll-head">
        <div>
          <h3 id="ll-plan-title">Choose a plan for Northwind Studio</h3>
          <p>You can switch plans at any time. Prices billed yearly.</p>
        </div>
        <div class="ll-needs" role="group" aria-label="Your needs">
          <label class="ll-need">Team size
            <select class="mv-select" id="ll-seats">
              <option value="2">1–3 people</option>
              <option value="8" selected>4–10 people</option>
              <option value="18">11–25 people</option>
              <option value="60">26–100 people</option>
            </select>
          </label>
          <label class="ll-need">Storage
            <select class="mv-select" id="ll-storage">
              <option value="5">5 GB</option>
              <option value="50" selected>50 GB</option>
              <option value="500">500 GB</option>
            </select>
          </label>
          <span class="ll-need">Security
            <label class="mv-choice"><input type="checkbox" role="switch" class="mv-switch" id="ll-sso"> SSO required</label>
          </span>
        </div>
      </header>
      <div class="ll-body">
        <mv-lifelines id="ll-plan" similar-label="teams of 4–10"
          question="Which plan should we get for the design team? We’re 8 people."
          share-url="https://app.northwind.example/plans/vote?options={shortlist}&amp;pick={pick}">
          <fieldset class="mv-choice-group" data-layout="grid" style="--mv-choice-min:17rem">
            <legend>Plan</legend>
            <label class="mv-choice-card">
              <input type="radio" class="mv-radio" name="ll-plan" value="starter">
              <span class="mv-choice-text"><span class="mv-choice-title">Starter</span><span class="mv-choice-description">Up to 3 seats · 5 GB · Community support</span></span>
              <span class="mv-radio-meta">$0</span>
            </label>
            <label class="mv-choice-card">
              <input type="radio" class="mv-radio" name="ll-plan" value="team" checked>
              <span class="mv-choice-text"><span class="mv-choice-title">Team</span><span class="mv-choice-description">Up to 25 seats · 100 GB · Shared libraries</span></span>
              <span class="mv-radio-meta">$12 <small>/ seat</small></span>
            </label>
            <label class="mv-choice-card">
              <input type="radio" class="mv-radio" name="ll-plan" value="business">
              <span class="mv-choice-text"><span class="mv-choice-title">Business</span><span class="mv-choice-description">Unlimited seats · 1 TB · SSO and audit log</span></span>
              <span class="mv-radio-meta">$24 <small>/ seat</small></span>
            </label>
            <label class="mv-choice-card">
              <input type="radio" class="mv-radio" name="ll-plan" value="enterprise">
              <span class="mv-choice-text"><span class="mv-choice-title">Enterprise</span><span class="mv-choice-description">From 50 seats · SSO and SCIM · 99.99% SLA</span></span>
              <span class="mv-radio-meta">Custom</span>
            </label>
          </fieldset>
        </mv-lifelines>
      </div>
    </section>

    <aside class="ll-side" aria-label="Demo controls">
      <h4>Replies you received <span class="mv-badge" data-variant="secondary" data-shape="pill" id="ll-count">0 votes</span></h4>
      <p>Your app collects answers from the shared link and feeds each one back with <code>addVote()</code>.</p>
      <div class="ll-votes">
        <button class="mv-button" data-variant="outline" data-size="sm" type="button" data-vote="team" data-from="Priya Raman" data-note="Team covers us, keep the budget for fonts.">Priya picks Team</button>
        <button class="mv-button" data-variant="outline" data-size="sm" type="button" data-vote="business" data-from="Marcus Olsen" data-note="We’ll want SSO once the agency joins.">Marcus picks Business</button>
        <button class="mv-button" data-variant="outline" data-size="sm" type="button" data-vote="team" data-from="Aiko Tanaka">Aiko picks Team</button>
      </div>
      <div class="ll-sep"></div>
      <button class="mv-button" data-variant="secondary" data-size="sm" type="button" id="ll-reset">Give lifelines back</button>
      <div class="ll-sep"></div>
      <h4>Events</h4>
      <ol class="ll-log" id="ll-log"><li>—</li></ol>
      <span class="mv-sr-only" role="status" id="ll-status"></span>
    </aside>
  </div>

  <!-- Variant: declarative data only (data-fit, data-share), two lifelines, no confidence readout -->
  <section class="ll-card ll-ship" aria-labelledby="ll-ship-title">
    <header class="ll-head">
      <div>
        <h3 id="ll-ship-title">Shipping</h3>
        <p>Order #48213 · 2 items · to Chicago, IL 60614</p>
      </div>
    </header>
    <div class="ll-body">
      <div class="ll-order">
        <dl>
          <div><dt>Trail runner, size 9</dt><dd>$128.00</dd></div>
          <div><dt>Merino socks, 2 pairs</dt><dd>$24.00</dd></div>
        </dl>
        <p class="ll-by"><span>You said it’s a gift for <b>Friday, October 2</b>. Options that won’t arrive in time can be set aside.</span></p>
      </div>
      <mv-lifelines lifelines="narrow, poll" threshold="0.7" show-confidence="false" similar-label="shoppers in Chicago" poll-note="Orders shipped to Illinois in the last 30 days." label="Not sure which one?">
        <fieldset class="mv-choice-group">
          <legend>Delivery</legend>
          <label class="mv-choice-card" data-fit="0" data-fit-reason="Arrives Oct 5–7, after Friday" data-share="38" data-share-similar="22">
            <input type="radio" class="mv-radio" name="ll-ship" value="economy">
            <span class="mv-choice-text"><span class="mv-choice-title">Economy</span><span class="mv-choice-description">6–8 business days</span></span>
            <span class="mv-radio-meta">Free</span>
          </label>
          <label class="mv-choice-card" data-fit="0.55" data-fit-reason="Arrives Sep 30–Oct 2, cutting it close" data-share="41" data-share-similar="44">
            <input type="radio" class="mv-radio" name="ll-ship" value="standard" checked>
            <span class="mv-choice-text"><span class="mv-choice-title">Standard</span><span class="mv-choice-description">3–5 business days</span></span>
            <span class="mv-radio-meta">$6.99</span>
          </label>
          <label class="mv-choice-card" data-fit="1" data-fit-reason="Arrives Monday, Sep 28" data-share="16" data-share-similar="27">
            <input type="radio" class="mv-radio" name="ll-ship" value="express">
            <span class="mv-choice-text"><span class="mv-choice-title">Express</span><span class="mv-choice-description">2 business days, tracked</span></span>
            <span class="mv-radio-meta">$14.99</span>
          </label>
          <label class="mv-choice-card" data-fit="0.85" data-fit-reason="Ready Thursday, Oct 1 at Lakeview Market" data-share="5" data-share-similar="7">
            <input type="radio" class="mv-radio" name="ll-ship" value="pickup">
            <span class="mv-choice-text"><span class="mv-choice-title">Pickup point</span><span class="mv-choice-description">Collect from a locker near you</span></span>
            <span class="mv-radio-meta">$3.99</span>
          </label>
        </fieldset>
      </mv-lifelines>
    </div>
  </section>
  <p class="ll-hint">Each lifeline works once · “Narrow it down” was already used on the plan picker · change your needs to re-check the set-aside plans</p>

  <script type="module">
    await customElements.whenDefined("mv-lifelines");
    const $ = (id) => document.getElementById(id);
    const ll = $("ll-plan");
    const PLANS = {
      starter: { seats: 3, storage: 5, sso: false, min: 1 },
      team: { seats: 25, storage: 100, sso: false, min: 1 },
      business: { seats: Infinity, storage: 1000, sso: true, min: 1 },
      enterprise: { seats: Infinity, storage: 5000, sso: true, min: 50 },
    };
    const readNeeds = () => ({ seats: Number($("ll-seats").value), storage: Number($("ll-storage").value), sso: $("ll-sso").checked });
    const gb = (n) => (n >= 1000 ? `${n / 1000} TB` : `${n} GB`);

    // The app's own fit logic: 0..1 per option, with the reason shown to the user.
    ll.needs = readNeeds();
    ll.narrow = ({ needs, options }) => options.map(({ value }) => {
      const p = PLANS[value];
      if (p.seats < needs.seats) return { value, fit: 0.1, reason: `Up to ${p.seats} seats, you need ${needs.seats}` };
      if (p.min > needs.seats) return { value, fit: 0.2, reason: `Starts at ${p.min} seats, you need ${needs.seats}` };
      if (p.storage < needs.storage) return { value, fit: 0.15, reason: `${gb(p.storage)} of storage, you need ${gb(needs.storage)}` };
      if (needs.sso && !p.sso) return { value, fit: 0.15, reason: "No single sign-on" };
      if (!needs.sso && p.sso) return { value, fit: 0.65, reason: "Fits, but you’d pay for SSO you don’t need" };
      return { value, fit: 0.92, reason: `Room for ${Number.isFinite(p.seats) ? p.seats : "unlimited"} seats and ${gb(p.storage)}` };
    });
    // What others chose: overall and for teams of the same size.
    const SEGMENTS = {
      2: ["teams of 1–3", { starter: 71, team: 22, business: 6, enterprise: 1 }],
      8: ["teams of 4–10", { starter: 9, team: 58, business: 29, enterprise: 4 }],
      18: ["teams of 11–25", { starter: 2, team: 47, business: 43, enterprise: 8 }],
      60: ["teams of 26–100", { starter: 1, team: 12, business: 52, enterprise: 35 }],
    };
    ll.stats = ({ needs }) => {
      const [similarLabel, similar] = SEGMENTS[needs.seats];
      return {
        everyone: { starter: 41, team: 33, business: 19, enterprise: 7 },
        similar, similarLabel,
        note: "Based on 12,480 workspaces created in the last 90 days.",
      };
    };

    const log = $("ll-log");
    const push = (html) => {
      if (log.firstElementChild?.textContent === "—") log.replaceChildren();
      const li = document.createElement("li");
      const [name, rest] = html;
      li.append(Object.assign(document.createElement("b"), { textContent: name }), ` ${rest}`);
      log.prepend(li);
      while (log.children.length > 5) log.lastElementChild.remove();
    };
    ll.addEventListener("mv-lifeline", (e) => push(["mv-lifeline", `${e.detail.lifeline}${e.detail.refresh ? " (refresh)" : ""}`]));
    ll.addEventListener("mv-lifeline-result", (e) => push(["result", `${e.detail.lifeline} · ${e.detail.confidence?.level ?? "no pick"}`]));
    ll.addEventListener("mv-change", (e) => push(["mv-change", `${e.detail.value} · ${e.detail.confidence?.level ?? "—"}`]));
    ll.addEventListener("mv-share", (e) => push(["mv-share", e.detail.method]));
    ll.addEventListener("mv-vote", (e) => {
      push(["mv-vote", `${e.detail.vote.from} → ${e.detail.vote.value}`]);
      const n = e.detail.votes.length;
      $("ll-count").textContent = `${n} vote${n === 1 ? "" : "s"}`;
    });

    // Start with one lifeline already spent, so the mechanic is visible.
    ll.use("narrow");

    for (const id of ["ll-seats", "ll-storage", "ll-sso"]) {
      $(id).addEventListener("change", () => {
        ll.needs = readNeeds();
        ll.refresh();
      });
    }
    document.querySelectorAll("#ll-demo [data-vote]").forEach((btn) => {
      btn.addEventListener("click", () => {
        ll.addVote({ value: btn.dataset.vote, from: btn.dataset.from, note: btn.dataset.note });
        btn.disabled = true;
      });
    });
    $("ll-reset").addEventListener("click", async () => {
      await ll.reset();
      document.querySelectorAll("#ll-demo [data-vote]").forEach((b) => { b.disabled = false; });
      $("ll-count").textContent = "0 votes";
      $("ll-status").textContent = "All lifelines are available again.";
    });
  </script>
</div>

Cultural reference

Who Wants to Be a Millionaire? — David Briggs, Mike Whitehill & Steven Knight (ITV) (1998, game show). A stuck contestant can use each lifeline once: one removes two wrong answers, one shows how the studio audience voted, one phones a trusted friend. In the UI, the same three helpers assist a hard product choice: they set aside the options that don't fit (with reasons), show what similar customers picked, and send the shortlist to a colleague for a vote. Each is visibly spent, and a confidence readout sums them up.

API

Attributes

Name	Type	Default	Description
`lifelines`	comma list of narrow \| poll \| ask	`narrow, poll, ask`	Which lifelines are offered, in toolbar order.
`uses`	number \| "unlimited" \| "narrow:1, poll:2, ask:unlimited"	`1`	How many times each lifeline can be used: one number for all, or per lifeline ("*" sets the default for the others). Up to five uses show as dots, more as a count.
`threshold`	number (0..1 or %)	`0.5`	Fit below which “Narrow it down” sets an option aside. Changing it re-runs a narrowing already done, without spending a use.
`keep`	number	`2`	Minimum number of options left visible after narrowing. The best-fitting of the would-be removals are kept to reach it. The checked option is never set aside; if it fits poorly it is flagged “Might not fit” instead.
`name`	string		Name of the radio group to manage when the element contains several. Defaults to the name of the first radio inside.
`label`	string	`Need a hand deciding?`	Visible label of the lifelines toolbar (also its accessible name). An empty value hides it.
`similar-label`	string	`people like you`	Name of the “people like you” segment, written lowercase to read inside sentences (“Chosen by 58% of teams of 4–10”). It is capitalized where it starts a label. A stats object's similarLabel wins.
`poll-note`	string		Where the statistics come from, shown in the “What others chose” note (“Orders shipped to Illinois in the last 30 days.”). A stats object's note wins.
`share-url`	URL template		Link added to the “Ask someone” message, for example your vote page. {shortlist} (comma-separated values still visible) and {pick} are replaced, URI-encoded. A url resolved by waitUntil wins.
`question`	string	`Could you help me decide? Here are the options I’m weighing:`	First line of the “Ask someone” message and title of the Web Share payload.
`show-confidence`	"true" \| "false"	`true`	"false" hides the confidence readout (the confidence property still works).
`data-fit / data-fit-reason`	number (0..1 or %) / string		On an option (its label, a [data-option] wrapper or the radio): declarative fit score and the reason shown to the user. Used when narrow() is not set or returns nothing for that option.
`data-share / data-share-similar`	number		On an option: share of everyone and of the “people like you” segment who chose it. Percentages, fractions (sum ≤ 1) or raw counts (sum above 100) are all normalized to percentages.
`data-option / data-label / data-summary`	attribute / string / string		On an option: data-option marks the wrapper when it isn't the radio's `<label>`; data-label and data-summary override the name and summary used in announcements and in the “Ask someone” message (defaults: .mv-choice-title, then .mv-choice-description · .mv-radio-meta).
`data-lifelines="toolbar \| notes \| readout"`	attribute		Place on your own empty containers to choose where the toolbar, the notes and the readout go. By default the toolbar and notes are prepended and the readout appended.
`data-lifeline-fit / data-lifeline-top / data-lifelines-hidden`	set by the component		On each option: fit \| poor \| out after narrowing, data-lifeline-top on the most chosen option, data-lifelines-hidden while an option is set aside and hidden (styleable).

Properties

Name	Type	Description
`narrow`	(context) => fits \| Promise`<fits>`	Your fit logic. context: { needs, value, options: [{ value, label, summary, element, data }], setAside }. Return [{ value, fit, reason }] or { [value]: fit \| { fit, reason } }, with fit in 0..1 (or a percentage).
`stats`	object \| (context) => object \| Promise`<object>`	What others chose: { everyone: { [value]: share }, similar?: { [value]: share }, similarLabel?, everyoneLabel?, note? }, a flat { [value]: share } map, or [{ value, share, similar }]. Setting it after the lifeline was used updates the bars in place.
`needs`	any	The user's stated needs, passed to narrow() and stats() as context.needs. Call refresh() after changing it.
`value`	string	Value of the checked radio. Setting it checks the matching radio (showing it again if it was set aside) without emitting mv-change.
`confidence`	{ value, level, label, pick, signals } \| null	Read-only. value 0..1 (null without signals), level "high" (≥ 0.7) \| "medium" (≥ 0.4) \| "low", signals: [{ kind: "fit" \| "crowd" \| "votes", value, tone: "good" \| "neutral" \| "bad", text }]. Weighted mean: fit 0.5, crowd 0.25 (the pick's share relative to the most chosen), votes 0.25.
`votes`	[{ value, from, note, at }]	Answers received through addVote() (read-only copy).
`setAside`	string[]	Values currently set aside by “Narrow it down” (read-only).
`strings`	Partial<Record<string, string>>	Overrides for every visible text and announcement (toolbarLabel, narrow, poll, ask, used, narrowTitle, narrowText, showAside, hideAside, tagOut, tagPoor, pollTitle, everyone, similar, mostChosen, mostChosenBy, askTitle, askText, share, copy, copied, question, askLeaning, askReply, askLink, answers, confidenceFor, levelHigh, levelMedium, levelLow, signalFit, signalCrowd, signalVotes, announce*…). English defaults.

Methods

Name	Description
`use(name)`	Runs a lifeline ("narrow" \| "poll" \| "ask") as if its button was pressed. Resolves to true when it ran; for ask, when its panel opened. A lifeline with nothing to show (no data) is not spent.
`usesLeft(name)`	Remaining uses of a lifeline (Infinity when unlimited).
`refresh()`	Re-runs the lifelines already used (narrow and poll) against the current needs and data, without spending a use. mv-lifeline fires with refresh: true.
`showAll(force?)`	Shows (true) or hides (false) the set-aside options; toggles without argument. Resolves to the new state.
`addVote({ value, from?, note? })`	Feeds back an answer from someone you asked. A second vote from the same person replaces the first. Returns false for an unknown value.
`clearVotes()`	Removes every vote.
`reset()`	Gives every lifeline back and clears narrowing, statistics and votes; set-aside options come back.
`openAsk() / closeAsk()`	Opens or closes the “Ask someone” panel.

Events

Name	Description
`mv-lifeline`	Cancelable, before a lifeline runs (for ask: when its panel opens for a new use). detail: { lifeline, refresh, usesLeft, context, waitUntil(promise) }. preventDefault() vetoes it (nothing is spent). Promises passed to waitUntil show a busy state; the last non-null value they resolve to is used as the data: fits for narrow, stats for poll, { text?, url? } for ask. A rejection spends nothing and emits mv-lifeline-error.
`mv-lifeline-result`	A lifeline ran. detail: { lifeline, refresh, result, confidence }. result: { setAside: [{ value, label, fit, reason }], fits } for narrow, { everyone, similar, top } for poll, { method, text, url } for ask.
`mv-lifeline-error`	A waitUntil promise, narrow() or stats() threw. detail: { lifeline, error }.
`mv-change`	The user picked another option. detail: { value, label, confidence }. The native change event still bubbles from the radio.
`mv-share`	The “Ask someone” message was shared or copied. detail: { method: "share" \| "copy", text, url }. The first one of a use spends it.
`mv-vote`	addVote() recorded an answer. detail: { vote, votes, confidence }.

Content structure

Name	Description
`(content)`	Your radio group: a `<fieldset>` of .mv-choice-card or .mv-choice labels, or any markup with native radios. Per-option results go into [data-lifelines-slot] if present, else .mv-choice-text, else the option wrapper.

CSS classes

Name	Description
`mv-lifelines-toolbar`	Labelled group holding -toolbar-label and .mv-lifelines-buttons.
`mv-lifelines-lifeline`	A lifeline button: -lifeline-icon, -lifeline-label, .mv-lifelines-uses (dots, count or “Used”). data-lifeline, data-state="available \| busy \| used", data-spent during the spend pulse.
`mv-lifelines-note / mv-lifelines-ask`	What each lifeline found, under the toolbar: -note-icon, -note-title, -note-text, -note-list, .mv-lifelines-legend. The ask panel adds .mv-lifelines-message (textarea), -ask-actions and .mv-lifelines-answers.
`mv-lifelines-aside`	Per-option results (aria-hidden, linked to the radio with aria-describedby): .mv-lifelines-tag, .mv-lifelines-reason[data-kind], .mv-lifelines-poll > .mv-lifelines-row[data-segment] (-row-label, .mv-lifelines-meter, -row-value), .mv-lifelines-votes.
`mv-lifelines-readout`	Confidence readout, data-level="high \| medium \| low \| none": -readout-title, .mv-lifelines-level, .mv-lifelines-gauge, .mv-lifelines-signals > li[data-tone].

CSS variables

Name	Default	Description
`--mv-lifelines-accent`	`var(--mv-accent)`	Lifeline icons, remaining-use dots, spend pulse and the “Moderate” level.
`--mv-lifelines-everyone`	`38% fg mixed into bg`	Bar color of the “everyone” segment.
`--mv-lifelines-similar`	`var(--mv-lifelines-accent)`	Bar color of the “people like you” segment.
`--mv-lifelines-good`	`var(--mv-success)`	Good-fit marks and the “Strong” level.
`--mv-lifelines-bad`	`var(--mv-warning)`	Poor-fit marks and the “Low” level.

Accessibility

The native radios are never replaced: the group keeps its <fieldset>/<legend>, arrow keys, required validation and form value. Lifelines are real <button>s in a group labelled by the visible toolbar label. Each button's name includes its state (“Narrow it down, 1 use left” / “, used” / “, working” with aria-busy). A spent lifeline keeps focus and gets aria-disabled="true"; pressing it announces that it was already used. The “Ask someone” button stays operable to reopen its panel, with aria-expanded and aria-controls. Results are announced once in a polite live region (“Set aside Starter and Enterprise. 2 options left. Confidence in Team: strong.”; “Most chosen by teams of 4–10: Team, 58%.”; “Priya Raman picked Team.”); selecting options never chatters. Per-option results are visible text, bars included (every bar has its percentage written next to it). They are aria-hidden inside the label so they don't lengthen the radio's name, and linked with aria-describedby, so a screen reader hears “Team, radio button, 2 of 4. Most chosen by teams of 4–10. Good fit: Room for 25 seats and 100 GB. Everyone 33%, teams of 4–10 58%”. Set-aside options leave the layout and the arrow-key cycle; the “Show them” toggle (aria-pressed, aria-controls pointing at the hidden options) brings them back selectable, marked “Set aside” with their reason, and the checked option is never hidden. The ask panel is a labelled region with a real <label> on its editable message; focus moves into it on open, and Escape or Close returns focus to the button. Share and copy results are announced, and if copying fails the message is selected for manual copy. Fit, crowd and confidence tones always come with an icon and words, never color alone. Reduced motion (OS or data-motion="reduce"): no FLIP, no bar growth, no spend pulse or busy blink. Forced colors: borders, use dots and bars fall back to system colors.