# Sign In (Notchset): prompt.md (v1.0.0)

- id: `sign-in` · version 1.0.0 · block · free
- category: Application UI
- build: Base UI (one set of files; its dependencies follow the build)
- install (this build): `npx shadcn@latest add https://beautiful-ui.dev/r/sign-in.json`
- npm dependencies: class-variance-authority@^0.7
- registry dependencies: utils, @beautiful-ui/input-otp, @beautiful-ui/segmented-control, https://beautiful-ui.dev/r/notchset-foundation.json
- docs: https://beautiful-ui.dev/components/sign-in
- The install command carries everything this item needs (files, CSS, tokens, npm and registry dependencies). Prefer it to copying source by hand.

Passwordless sign-in and sign-up that routes enterprise users to their identity provider: an SSO domain unrolls its organisation and the key becomes CONTINUE WITH the provider; otherwise a 6-digit code that pastes and submits itself, with tries left and a rolling resend; passkey and social sign-in with the last one used marked on the device; an ink brand panel beside it.

## Build it
- Stack: React 19 (`ref` is a plain prop), TypeScript, Tailwind CSS v4 utilities, a shadcn-initialised project with the `@/*` alias.
- Packages: `class-variance-authority@^0.7`.
- Files: `components/ui/notchset/blocks/sign-in.tsx`; shared code: `lib/beautiful-ui/notchset/instrument.tsx`, `lib/beautiful-ui/notchset/root.ts`, `lib/beautiful-ui/notchset/button-variants.ts`, `lib/beautiful-ui/notchset/field-classes.ts`.
- Registry dependencies, installed with it automatically: shadcn `utils` (cn), `input-otp`, `segmented-control`, `notchset-foundation`.
- Builds: one set of files for both, but its dependencies come in Base UI and Radix builds. Install the one that matches the project (see Install): a free item's bare URL installs the Base UI build of it and its dependencies.
- Exports to keep: `SignIn`, and every exported type.
- CSS: the install adds the notchset foundation (tokens, keyframes, motion levels) to your global stylesheet once. Nothing to import by hand.
- Re-running `add` (or `--overwrite`) re-applies those rules: put overrides in your own CSS, never in the installed rules.
- Tokens: retheme with the `--notchset-*` custom properties (`--notchset-check`, `--notchset-control-edge`, `--notchset-draw-from`, `--notchset-ease-bloom`, `--notchset-ease-glide`, `--notchset-ease-key-down`, `--notchset-ease-key-up`, `--notchset-ease-travel`, `--notchset-fade`, `--notchset-focus-color`, `--notchset-focus-inset`, `--notchset-grow-to`, `--notchset-key-down`, `--notchset-key-up`, `--notchset-life-from`, `--notchset-life-ms`, `--notchset-node-blink`, `--notchset-node-bloom`, `--notchset-node-delay`, `--notchset-plate-color`, `--notchset-rise-from`, `--notchset-rule`, `--notchset-scan-to`, `--notchset-scroll`, `--notchset-signal`, `--notchset-sweep-to`, `--notchset-travel`). Never add Tailwind colour classes inside the component.

```tsx
import { SignIn } from "@/components/ui/notchset/blocks/sign-in";
```

## Parts

| Part | data-slot | What it is for |
|---|---|---|
| `SignIn` | `sign-in` | Email, code and done steps, with SSO and providers. |

Style a part with `[data-slot="<slot>"]` selectors or its `className`; keep the attributes when editing.

## Sound
- Keep every `data-slot` and `data-sound` attribute: the sound layer reads them.
- Installing this item adds no audio. Nothing plays until the app mounts `SoundProvider` once (install: `npx shadcn@latest add https://beautiful-ui.dev/r/notchset-sound.json`, import from `@/components/ui/notchset/sound-provider`); `useSound()` gives `muted` and `setMuted` for a mute control. Without a provider the audio engine never loads.

## Match the original
- Read `components/ui/notchset/blocks/sign-in.tsx` as the reference implementation before changing or recreating anything, and match it: sizes, colours per theme, motion timings, copy and behaviour.
- If you deviate (a prop you can't honour, a style you changed, a dependency you swapped), say so in your reply, part by part.
- Keep the accessibility contract, the keyboard map and the motion levels listed below.

## Use it when
- sign in, login, sign up, passwordless, magic code, one-time code, otp login, sso, single sign-on, okta, passkey, auth page, Notchset
- A product's sign-in and sign-up page
- Teams whose admins enforce single sign-on

### Not when
- Passwords are required: add a password step of your own
- A checkout's guest email: a plain field is enough

## Mistakes
- Decide SSO on the server too: the client only routes
- Rate-limit code sends and attempts, and expire codes after 10 minutes
- Never use LAST USED to reveal whether an account exists

## Usage

```tsx
import { SignIn } from "@/components/ui/notchset/blocks/sign-in";

export function Login() {
  return (
    <SignIn
      brand={{ name: "Relay" }}
      onRequestCode={async (email) => {
        await fetch("/api/auth/code", { method: "POST", body: JSON.stringify({ email }) });
      }}
      onVerify={async (email, code) => {
        const res = await fetch("/api/auth/verify", { method: "POST", body: JSON.stringify({ email, code }) });
        return res.ok;
      }}
      next={{ label: "OPENING /AGENTS", onOpen: () => location.assign("/agents") }}
    />
  );
}
```

## Props

| Prop | Type | Default | What it does |
|---|---|---|---|
| `onRequestCode / onVerify` | `(email, signUp) => Promise / (email, code) => Promise<boolean>` |  | Send a code (the same answer whether or not the account exists) and check it. |
| `detectSso / onSso` | `(email) => Promise<SsoMatch \| null> / (email, sso) => Promise<string>` |  | Route an SSO domain to its provider; onSso resolves with who signed in. |
| `providers` | `{ id, label, icon?, onSignIn() => Promise<string> }[]` |  | Passkey and social sign-in; the last one used is marked on this device. |
| `next` | `{ label, onOpen? }` |  | Where the done state goes ("OPENING /AGENTS"). |
| `brand / aside / termsLink / footer` | `…` |  | The mark, the ink panel (hidden under 760px), the terms link in sign-up and the footer line. |

Full docs: https://beautiful-ui.dev/components/sign-in

## Customising
- Colours: the component reads your shadcn tokens (`--background`, `--foreground`, `--border` …), refined by the `--notchset-*` tokens. The signal colour is `--notchset-signal` (it falls back to `--destructive`). Set tokens on `:root`, or on any container to retheme one area.
- Dark mode follows the `.dark` class on an ancestor (the shadcn and next-themes convention).
- Update later by re-running the install with `--overwrite` (review the diff if you edited it). Changelog: https://beautiful-ui.dev/r/changelog.json

## Keyboard

| Keys | Action |
|---|---|
| Enter | Continue from the email |
| ← → | Switch between sign in and create account |
| Type or paste | The code submits itself at 6 digits |

## Performance

- The SSO lookup waits 280ms after typing stops, and only the newest answer is used.

## Responsive

- The brand panel hides under 760px (container width); the form fits 320px.

## Motion inventory

| Interaction | What moves |
|---|---|
| Mode and step | Content rises 6px as it fades in (300ms) |
| SSO | The organisation card unrolls (360ms) and the key's label changes |
| Code | Digits pop in; a wrong code shakes and clears; resend rolls down |
| Working | The scanner on whichever key is working |

## Accessibility contract (preserve when editing)
- The section is named by its step; fields have labels, mark invalid input (aria-invalid) and announce hints (aria-live)
- The terms checkbox is a real checkbox (role, aria-checked); errors that block a step are alerts
- The code is one real input (one-time-code autocomplete, numeric) under the cells, so paste and autofill work
- The brand panel is decorative (aria-hidden)

## Install

Base UI project (a base-* style in components.json):

```bash
npx shadcn@latest add https://beautiful-ui.dev/r/sign-in.json
```

Radix project (a radix-*, new-york or default style):

```bash
npx shadcn@latest add https://beautiful-ui.dev/r/radix-nova/sign-in.json
```

Or add the `@beautiful-ui` registry to components.json and run `npx shadcn@latest add @beautiful-ui/sign-in`: the CLI picks the build from your style.

## Credits
- Built on shadcn/ui (https://ui.shadcn.com)

## Source (Base UI build)

### components/ui/notchset/blocks/sign-in.tsx

```tsx
"use client";

import * as React from "react";
import { cn } from "@/lib/utils";
import { inputClass } from "@/lib/beautiful-ui/notchset/field-classes";
import { buttonVariants } from "@/lib/beautiful-ui/notchset/button-variants";
import { InputOTPVerify } from "@/components/ui/notchset/input-otp";
import { SegmentedControl } from "@/components/ui/notchset/segmented-control";
import { NOTCHSET_ROOT, OWN_SOUND, Scanner, playCue } from "@/lib/beautiful-ui/notchset/instrument";

/*
 * Notchset Sign In (a block, one file for both builds). Passwordless sign-in and sign-up that routes
 * enterprise users to their identity provider: email first; an SSO domain unrolls its organisation and
 * the key becomes CONTINUE WITH <IDP>; otherwise a 6-digit code (the Input OTP verify) that pastes and
 * submits itself; passkey and social sign-in beside it, the last one used marked on this device only.
 * Every decision is your server's (the promises you pass); the block only reflects them.
 */

export type SsoMatch = { org: string; initials: string; domain: string; provider: string; note?: string };
export type SignInProvider = { id: string; label: string; icon?: React.ReactNode; onSignIn: () => Promise<string> };

export type SignInProps = Omit<React.ComponentProps<"section">, "children"> & {
  brand: { name: string; mark?: React.ReactNode };
  /** Look up an SSO-enforced domain (decide on the server; this only routes the UI). */
  detectSso?: (email: string) => Promise<SsoMatch | null>;
  /** Send a code (the same answer whether or not the account exists). */
  onRequestCode: (email: string, signUp: { name: string } | null) => Promise<unknown>;
  /** Check a code; resolve true to sign in. */
  onVerify: (email: string, code: string) => Promise<boolean>;
  /** Hand off to the identity provider; resolve with "who" for the done state. */
  onSso?: (email: string, sso: SsoMatch) => Promise<string>;
  /** Passkey and social sign-in; each resolves with "who" for the done state. */
  providers?: readonly SignInProvider[];
  /** Where the done state says it's going ("OPENING /AGENTS"), and what START OVER does. */
  next: { label: string; onOpen?: () => void };
  /** The ink panel beside the form (hidden under 760px). */
  aside?: { headline: string; body: string; status?: string; news?: string };
  termsLink?: React.ReactNode;
  footer?: React.ReactNode;
  /** Where the last provider used is remembered (this device only; never used to reveal accounts). */
  lastUsedKey?: string;
};

const EMAIL = /^[^\s@]+@[^\s@]+\.[^\s@]{2,}$/;
const label = "font-mono text-[10px] font-medium tracking-[0.12em] uppercase";
const field = cn(inputClass, "h-11 font-sans text-[14px]");

/** The provider used last on this device (localStorage; null on the server and when storage is blocked). */
function useLastUsed(key: string) {
  const [, bump] = React.useReducer((n: number) => n + 1, 0);
  const value = React.useSyncExternalStore(
    (cb) => {
      window.addEventListener("storage", cb);
      return () => window.removeEventListener("storage", cb);
    },
    () => {
      try {
        return localStorage.getItem(key);
      } catch {
        return null;
      }
    },
    () => null,
  );
  const remember = (id: string) => {
    try {
      localStorage.setItem(key, id);
    } catch {}
    bump();
  };
  return [value, remember] as const;
}

function SignIn({ brand, detectSso, onRequestCode, onVerify, onSso, providers = [], next, aside, termsLink, footer, lastUsedKey = `notchset-last-sign-in`, className, ...props }: SignInProps) {
  const [mode, setMode] = React.useState<"in" | "up">("in");
  const [step, setStep] = React.useState<"email" | "code" | "done">("email");
  const [email, setEmail] = React.useState("");
  const [name, setName] = React.useState("");
  const [terms, setTerms] = React.useState(false);
  const [error, setError] = React.useState<{ field: "email" | "name" | "terms" | "form"; text: string } | null>(null);
  // The SSO answer belongs to the address it was looked up for: a newer address ignores it.
  const [ssoFor, setSsoFor] = React.useState<{ email: string; match: SsoMatch | null }>({ email: "", match: null });
  const [busy, setBusy] = React.useState<string | null>(null);
  const [who, setWho] = React.useState("");
  const [last, remember] = useLastUsed(lastUsedKey);
  const root = React.useRef<HTMLElement>(null);
  const emailRef = React.useRef<HTMLInputElement>(null);

  // SSO lookup as the address settles (280ms after typing stops); the newest answer wins.
  const lookup = React.useRef(0);
  React.useEffect(() => {
    const value = email.trim();
    if (!detectSso || mode !== "in" || !EMAIL.test(value)) return;
    const me = ++lookup.current;
    const t = setTimeout(() => {
      detectSso(value).then(
        (match) => me === lookup.current && setSsoFor({ email: value, match }),
        () => me === lookup.current && setSsoFor({ email: value, match: null }),
      );
    }, 280);
    return () => clearTimeout(t);
  }, [email, mode, detectSso]);
  const sso = mode === "in" && ssoFor.email === email.trim() ? ssoFor.match : null;

  const reset = () => {
    setStep("email");
    setError(null);
    setBusy(null);
  };
  const succeed = (whoLine: string, provider?: string) => {
    playCue(root.current, "done");
    if (provider) remember(provider);
    setWho(whoLine);
    setStep("done");
    setBusy(null);
  };
  const submit = async (e?: React.FormEvent) => {
    e?.preventDefault();
    if (busy) return;
    const value = email.trim();
    if (mode === "up" && !name.trim()) return fail("name", "ENTER YOUR NAME");
    if (!EMAIL.test(value)) return fail("email", value ? "THAT EMAIL LOOKS INCOMPLETE" : "ENTER YOUR WORK EMAIL");
    if (mode === "up" && !terms) return fail("terms", "ACCEPT THE TERMS TO CONTINUE");
    setError(null);
    if (sso && onSso && mode === "in") {
      setBusy("sso");
      try {
        succeed(await onSso(value, sso), "sso");
      } catch {
        fail("form", `COULDN’T REACH ${sso.provider.toUpperCase()} · TRY AGAIN`);
        setBusy(null);
      }
      return;
    }
    setBusy("code");
    try {
      await onRequestCode(value, mode === "up" ? { name: name.trim() } : null);
      playCue(root.current, "tick");
      setStep("code");
    } catch {
      fail("form", "COULDN’T SEND A CODE · TRY AGAIN");
    }
    setBusy(null);
  };
  const fail = (f: "email" | "name" | "terms" | "form", text: string) => {
    playCue(root.current, "signal");
    setError({ field: f, text });
    if (f === "email") emailRef.current?.focus();
  };
  const viaProvider = async (p: SignInProvider) => {
    if (busy) return;
    setBusy(p.id);
    setError(null);
    try {
      succeed(await p.onSignIn(), p.id);
    } catch {
      fail("form", `${p.label.toUpperCase()} DIDN’T FINISH · TRY AGAIN`);
      setBusy(null);
    }
  };

  const valid = EMAIL.test(email.trim());
  const emailHint = error?.field === "email" ? error.text : sso && mode === "in" ? "SSO DETECTED" : valid ? "✓" : "";
  const copy =
    step === "code"
      ? { eyebrow: "CHECK YOUR INBOX", title: "Enter the code", sub: `We sent a 6-digit code to ${email.trim()}. It expires in 10 minutes.` }
      : step === "done"
        ? { eyebrow: "SIGNED IN", title: "You're in", sub: "" }
        : mode === "in"
          ? { eyebrow: `SIGN IN TO ${brand.name.toUpperCase()}`, title: "Welcome back", sub: "No password: we email you a code, or your company's sign-in takes over." }
          : { eyebrow: `CREATE A ${brand.name.toUpperCase()} ACCOUNT`, title: "Start in a minute", sub: "Your name and work email. We send a code to confirm it." };

  return (
    <section {...NOTCHSET_ROOT} ref={root} data-slot="sign-in" aria-label={copy.eyebrow} className={cn("@container box-border flex min-h-[620px] overflow-hidden border border-solid border-foreground bg-background text-foreground", className)} {...props}>
      <div className="flex min-w-0 flex-1 flex-col gap-5 overflow-y-auto px-8 py-7 @max-[480px]:px-5">
        <div className="flex flex-wrap items-center justify-between gap-3 gap-y-1">
          <span className="flex items-center gap-2 font-mono text-[10px] font-medium tracking-[0.14em] uppercase">
            {brand.mark ?? <span aria-hidden className="size-5 bg-foreground" />}
            {brand.name}
          </span>
          {step === "email" && (
            <SegmentedControl
              aria-label="Mode"
              size="sm"
              segment={96}
              options={[
                { value: "in", label: "SIGN IN" },
                { value: "up", label: "CREATE ACCOUNT" },
              ]}
              value={mode}
              onValueChange={(v) => {
                setMode(v as "in" | "up");
                setError(null);
              }}
            />
          )}
        </div>
        <div key={`${mode}-${step}`} className="mx-auto flex w-full max-w-[400px] flex-1 flex-col justify-center gap-[18px] motion-safe:animate-[notchset-rise_300ms_var(--notchset-ease-settle)_both]">
          <div className="flex flex-col gap-2">
            <span className="font-mono text-[10px] tracking-[0.12em] whitespace-nowrap text-muted-foreground">{copy.eyebrow}</span>
            <h2 className="m-0 text-[40px] leading-[0.9] font-extrabold uppercase [font-stretch:62%] [text-wrap:balance]">{copy.title}</h2>
            {copy.sub && <p className="m-0 text-[14px] leading-normal text-muted-foreground [text-wrap:pretty]">{copy.sub}</p>}
          </div>

          {step === "email" && (
            <form noValidate onSubmit={submit} className="flex flex-col gap-3">
              {mode === "up" && (
                <label className="flex flex-col gap-1.5">
                  <span className={cn(label, "flex justify-between")}>
                    <span>NAME</span>
                    {error?.field === "name" && <span className="font-normal text-[var(--notchset-signal-text,var(--destructive))]">{error.text}</span>}
                  </span>
                  <input aria-label="Name" aria-invalid={error?.field === "name" || undefined} value={name} onChange={(e) => setName(e.target.value)} autoComplete="name" placeholder="Maya Kerr" spellCheck={false} className={cn(field, error?.field === "name" ? "border-[var(--notchset-signal,var(--destructive))]" : "border-[var(--notchset-control-edge,var(--input))]")} />
                </label>
              )}
              <label className="flex flex-col gap-1.5">
                <span className={cn(label, "flex justify-between")}>
                  <span>WORK EMAIL</span>
                  <span aria-live="polite" className={cn("font-normal", error?.field === "email" ? "text-[var(--notchset-signal-text,var(--destructive))]" : "text-foreground")}>
                    {emailHint}
                  </span>
                </span>
                <input
                  ref={emailRef}
                  type="email"
                  aria-label="Work email"
                  aria-invalid={error?.field === "email" || undefined}
                  value={email}
                  readOnly={Boolean(busy)}
                  onChange={(e) => {
                    setEmail(e.target.value);
                    if (error?.field === "email" || error?.field === "form") setError(null);
                  }}
                  autoComplete="email"
                  placeholder="name@company.com"
                  spellCheck={false}
                  className={cn(field, error?.field === "email" ? "border-[var(--notchset-signal,var(--destructive))]" : "border-[var(--notchset-control-edge,var(--input))]")}
                />
              </label>
              <div className={cn("grid grid-cols-[minmax(0,1fr)] transition-[grid-template-rows] ease-(--notchset-ease-unfold)", sso && mode === "in" ? "grid-rows-[1fr] duration-(--notchset-unfold)" : "grid-rows-[0fr] duration-(--notchset-fold)")}>
                <div className="min-h-0 overflow-hidden">
                  {sso && (
                    <div className="flex items-center gap-2.5 border border-solid border-foreground bg-[var(--notchset-field,var(--background))] px-3 py-2.5">
                      <span aria-hidden className="flex size-6 flex-none items-center justify-center bg-foreground font-mono text-[10px] font-medium text-background">
                        {sso.initials}
                      </span>
                      <span className="flex flex-1 flex-col gap-0.5">
                        <span className="text-[13px] font-medium">{sso.org} uses single sign-on</span>
                        <span className="font-mono text-[10px] tracking-[0.08em] text-muted-foreground uppercase">
                          {sso.domain} · {sso.provider} · {sso.note ?? "REQUIRED BY YOUR ADMIN"}
                        </span>
                      </span>
                    </div>
                  )}
                </div>
              </div>
              {mode === "up" && (
                <button
                  {...OWN_SOUND}
                  type="button"
                  role="checkbox"
                  aria-checked={terms}
                  onClick={() => {
                    playCue(root.current, "tick");
                    setTerms((t) => !t);
                    if (error?.field === "terms") setError(null);
                  }}
                  className={cn(`notchset-focus`, "flex cursor-pointer items-start gap-2.5 border-0 bg-transparent p-0 text-start text-foreground [--notchset-focus-inset:-3px]")}
                >
                  <span className={cn("mt-px flex size-4 flex-none items-center justify-center border border-solid", error?.field === "terms" ? "border-[var(--notchset-signal,var(--destructive))]" : "border-foreground", terms ? "bg-foreground" : "bg-transparent")}>
                    <svg aria-hidden width="10" height="10" viewBox="0 0 10 10">
                      <path d="M1.8 5.2 L4 7.4 L8.3 2.8" fill="none" className="stroke-background transition-[stroke-dashoffset] duration-(--notchset-check) ease-(--notchset-ease-check)" strokeWidth="1.6" pathLength={1} strokeDasharray={1} style={{ strokeDashoffset: terms ? 0 : 1 }} />
                    </svg>
                  </span>
                  <span className="text-[13px] leading-[1.45] text-muted-foreground">
                    I agree to the {termsLink ?? "terms and privacy policy"}.
                    {error?.field === "terms" && <span className="block font-mono text-[10px] tracking-[0.08em] text-[var(--notchset-signal-text,var(--destructive))]">{error.text}</span>}
                  </span>
                </button>
              )}
              <button
                {...OWN_SOUND}
                type="submit"
                aria-busy={busy === "code" || busy === "sso" || undefined}
                className={cn(`notchset-focus`, buttonVariants({ variant: "default", size: "lg" }), "justify-center gap-2 [--notchset-focus-inset:-4px]")}
              >
                {busy === "code" || busy === "sso" ? <Scanner height={9} /> : null}
                {busy === "code" ? "SENDING CODE" : busy === "sso" && sso ? `OPENING ${sso.provider.toUpperCase()}` : sso && mode === "in" ? `CONTINUE WITH ${sso.provider.toUpperCase()}` : mode === "up" ? "CREATE ACCOUNT" : "EMAIL ME A CODE"}
              </button>
              {error?.field === "form" && (
                <span role="alert" className="font-mono text-[10px] tracking-[0.08em] text-[var(--notchset-signal-text,var(--destructive))]">
                  {error.text}
                </span>
              )}
              {mode === "in" && providers.length > 0 && (
                <>
                  <div className="flex items-center gap-2.5 font-mono text-[10px] tracking-[0.14em] text-muted-foreground">
                    <span className="h-px flex-1 bg-[var(--notchset-rule,var(--border))]" />
                    OR
                    <span className="h-px flex-1 bg-[var(--notchset-rule,var(--border))]" />
                  </div>
                  <div className="grid gap-1.5" style={{ gridTemplateColumns: `repeat(${Math.min(3, providers.length)}, minmax(0, 1fr))` }}>
                    {providers.map((p) => (
                      <button
                        key={p.id}
                        {...OWN_SOUND}
                        type="button"
                        aria-busy={busy === p.id || undefined}
                        onClick={() => viaProvider(p)}
                        className={cn(
                          `notchset-focus`,
                          "relative flex h-10 cursor-pointer items-center justify-center gap-1.5 border border-solid bg-transparent font-mono text-[10px] font-medium tracking-[0.1em] whitespace-nowrap text-foreground transition-colors duration-(--notchset-fade) ease-(--notchset-ease-fade) [--notchset-focus-inset:-4px] hover:bg-accent",
                          last === p.id ? "border-foreground" : "border-[var(--notchset-control-edge,var(--input))]",
                        )}
                      >
                        {busy === p.id ? <Scanner height={8} /> : p.icon}
                        {p.label}
                        {last === p.id && <span className="absolute -top-2 end-1.5 bg-foreground px-1 font-mono text-[10px] leading-4 text-background">LAST USED</span>}
                      </button>
                    ))}
                  </div>
                </>
              )}
            </form>
          )}

          {step === "code" && (
            <div className="flex flex-col gap-3">
              <InputOTPVerify
                ariaLabel="Sign-in code"
                pattern="^[0-9]+$"
                onComplete={async (code) => {
                  const ok = await onVerify(email.trim(), code);
                  if (ok) setTimeout(() => succeed(email.trim()), 450);
                  return ok;
                }}
                onResend={() => void onRequestCode(email.trim(), mode === "up" ? { name: name.trim() } : null).catch(() => fail("form", "COULDN’T SEND A CODE · TRY AGAIN"))}
                labels={{ wrong: (left) => `THAT CODE DIDN’T MATCH · ${left} TRIES LEFT`, locked: "TOO MANY TRIES · REQUEST A NEW CODE", ok: "SIGNED IN" }}
              />
              {error?.field === "form" && (
                <span role="alert" className="font-mono text-[10px] tracking-[0.08em] text-[var(--notchset-signal-text,var(--destructive))]">
                  {error.text}
                </span>
              )}
              <button {...OWN_SOUND} type="button" onClick={reset} className={cn(`notchset-focus`, "h-6 cursor-pointer self-start border-0 bg-transparent p-0 font-mono text-[10px] font-medium tracking-[0.1em] text-foreground underline underline-offset-[3px] [--notchset-focus-inset:-3px]")}>
                ← USE A DIFFERENT EMAIL
              </button>
            </div>
          )}

          {step === "done" && (
            <div role="status" className="flex flex-col gap-3.5">
              <div className="flex items-center gap-3 border border-solid border-foreground p-3">
                <span aria-hidden className="flex size-9 items-center justify-center bg-foreground">
                  <svg width="16" height="16" viewBox="0 0 16 16">
                    <path d="M3 8.4 L6.4 11.6 L13 4.6" fill="none" className="stroke-background" strokeWidth="1.8" pathLength={1} strokeDasharray={1} style={{ strokeDashoffset: 0 }} />
                  </svg>
                </span>
                <span className="flex flex-1 flex-col gap-1">
                  <span className="text-[14px] font-medium">Signed in as {who}</span>
                  <span className="flex items-center gap-2 font-mono text-[10px] tracking-[0.1em] text-muted-foreground">
                    <Scanner height={8} /> {next.label}
                  </span>
                </span>
              </div>
              <button
                {...OWN_SOUND}
                type="button"
                onClick={() => {
                  playCue(root.current, "tap");
                  setEmail("");
                  reset();
                  next.onOpen?.();
                }}
                className={cn(`notchset-focus`, "h-6 cursor-pointer self-start border-0 bg-transparent p-0 font-mono text-[10px] font-medium tracking-[0.1em] text-foreground underline underline-offset-[3px] [--notchset-focus-inset:-3px]")}
              >
                START OVER
              </button>
            </div>
          )}
        </div>
        <div className="flex flex-wrap justify-between gap-3 font-mono text-[10px] tracking-[0.1em] whitespace-nowrap text-muted-foreground gap-y-1">{footer}</div>
      </div>
      {aside && (
        <aside aria-hidden className="box-border flex w-[340px] flex-none flex-col justify-between bg-foreground p-7 text-background @max-[760px]:hidden">
          <span aria-hidden className="size-6 border border-solid border-background" />
          <div className="flex flex-col gap-3">
            <span className="text-[44px] leading-[0.9] font-extrabold uppercase [font-stretch:62%]">{aside.headline}</span>
            <span className="text-[13.5px] leading-normal opacity-75">{aside.body}</span>
          </div>
          {(aside.status || aside.news) && (
            <div className="flex flex-col gap-2.5 border-0 border-t border-solid border-background/40 pt-3.5 font-mono text-[10px] tracking-[0.1em]">
              {aside.status && (
                <span className="flex items-center gap-2">
                  <span className="size-1.5 rounded-full bg-background motion-safe:animate-pulse" />
                  {aside.status}
                </span>
              )}
              {aside.news && <span className="opacity-70">{aside.news}</span>}
            </div>
          )}
        </aside>
      )}
    </section>
  );
}

export { SignIn };
```

### lib/beautiful-ui/notchset/instrument.tsx

```tsx
"use client";

import * as React from "react";
import { createPortal } from "react-dom";
import { cn } from "@/lib/utils";

/*
 * Notchset instrument parts, shared by every member of a pack: the node (a round light that reports
 * state), the legend printed above a control, the plate a key presses onto, the traced check, the
 * five-tick scanner, and the glyph flip that lands a changed label left to right. Nodes and checks
 * are inline SVG (round at every DPR); the CSS lives in the Notchset foundation. Also: the one motion
 * policy (reduced motion or a data-motion="off" ancestor), ref composition, the portal container
 * and the sound attributes every Notchset root carries.
 */

// ---------------------------------------------------------------------------------------------
// Motion, refs, portals, sound
// ---------------------------------------------------------------------------------------------

/**
 * Whether motion is off for an element, kept live: it follows the OS reduced-motion setting and any
 * data-motion attribute change above it, so a preference switched mid-playback stops decoration at once.
 */
export function useMotionOff(ref: React.RefObject<Element | null>) {
  const [off, setOff] = React.useState(false);
  React.useEffect(() => {
    const read = () => setOff(motionOff(ref.current));
    const r = requestAnimationFrame(read);
    const mq = window.matchMedia?.("(prefers-reduced-motion: reduce)");
    mq?.addEventListener?.("change", read);
    const mo = new MutationObserver(read);
    mo.observe(document.documentElement, { attributes: true, attributeFilter: ["data-motion"], subtree: true });
    return () => {
      cancelAnimationFrame(r);
      mq?.removeEventListener?.("change", read);
      mo.disconnect();
    };
  }, [ref]);
  return off;
}

/**
 * The microphone, or a rejection after `timeoutMs` (a prompt left open, a denied permission). A stream
 * that arrives after the timeout is stopped at once, so a late "Allow" never leaves the mic on.
 */
export function requestMic(timeoutMs = 5000): Promise<MediaStream> {
  if (typeof navigator === "undefined" || !navigator.mediaDevices?.getUserMedia) return Promise.reject(new Error("no mic"));
  const ask = navigator.mediaDevices.getUserMedia({ audio: true });
  return new Promise((resolve, reject) => {
    let late = false;
    const t = setTimeout(() => {
      late = true;
      reject(new Error("timeout"));
    }, timeoutMs);
    ask.then(
      (stream) => {
        clearTimeout(t);
        if (late) stream.getTracks().forEach((track) => track.stop());
        else resolve(stream);
      },
      (err) => {
        clearTimeout(t);
        reject(err);
      },
    );
  });
}

/** True under prefers-reduced-motion or inside a data-motion="off" scope. Checked when an effect runs. */
export function motionOff(el: Element | null | undefined) {
  if (typeof window === "undefined") return true;
  if (window.matchMedia?.("(prefers-reduced-motion: reduce)").matches) return true;
  return Boolean(el?.closest('[data-motion="off"]'));
}

function assignRef<T>(ref: React.Ref<T> | undefined, node: T | null): () => void {
  if (typeof ref === "function") {
    const cleanup = ref(node);
    return typeof cleanup === "function" ? cleanup : () => ref(null);
  }
  if (ref) (ref as React.RefObject<T | null>).current = node;
  return () => {
    if (ref) (ref as React.RefObject<T | null>).current = null;
  };
}

/**
 * Puts text on the clipboard. Resolves true once it is there and false when the browser refuses (no
 * permission, an insecure page, no clipboard API), so a "copied" state is only ever shown for a copy.
 */
export async function copyText(text: string): Promise<boolean> {
  try {
    await navigator.clipboard.writeText(text);
    return true;
  } catch {
    return false;
  }
}

/** The glide easing shared by travelling marks (selection blocks, highlights, runs). */
export const GLIDE = "cubic-bezier(.65,0,.35,1)";

/** Base UI's className may be a function of state: merges ours with it in either form. */
export const withClass =
  <S,>(base: string, className: string | ((state: S) => string | undefined) | undefined) =>
  (state: S) =>
    cn(base, typeof className === "function" ? className(state) : className);

/** Composes two refs, keeping React 19 ref cleanups. */
export function useComposedRefs<T>(a: React.Ref<T> | undefined, b: React.Ref<T> | undefined): React.RefCallback<T> {
  return React.useCallback(
    (node: T | null) => {
      const release = [assignRef(a, node), assignRef(b, node)];
      return () => release.forEach((f) => f());
    },
    [a, b],
  );
}

/**
 * Runs each step on its own animation frame, in order (the first on the next frame), and returns one
 * cancel that stops whichever frame is pending. A no-op step just waits a frame: frames(set pre, wait,
 * go) lets the browser paint the start state before the transition begins.
 */
export function frames(...steps: (() => void)[]): () => void {
  let id = 0;
  let i = 0;
  const tick = () => {
    steps[i++]?.();
    if (i < steps.length) id = requestAnimationFrame(tick);
  };
  id = requestAnimationFrame(tick);
  return () => cancelAnimationFrame(id);
}
export const wait = () => {};

let idSeq = 0;
/** A unique id for something the user creates (a milestone, a note): random where the browser can, else a counter. */
export const newId = () => (typeof crypto !== "undefined" && "randomUUID" in crypto ? crypto.randomUUID() : `id-${Date.now()}-${++idSeq}`);

/**
 * True while an input method (Japanese, Chinese, Korean…) is composing: Enter, Tab and delimiters
 * then belong to the composition, not to the component. keyCode 229 covers Safari's late flag.
 */
export function composing(e: React.KeyboardEvent | KeyboardEvent) {
  const native = "nativeEvent" in e ? e.nativeEvent : e;
  return native.isComposing || native.keyCode === 229;
}

const hotkeyOwners = new Map<string, number[]>();
let hotkeySeq = 0;
/**
 * A page-wide shortcut ("/" or "mod+k", mod being ⌘ or Ctrl) with a single owner: when several
 * components claim the same key, only the one mounted last answers, so one press never opens two.
 * A plain key is ignored while typing in a field.
 */
export function useHotkey(combo: string | undefined, run: () => void) {
  const latest = useLatest(run);
  React.useEffect(() => {
    if (!combo) return;
    const me = ++hotkeySeq;
    const stack = hotkeyOwners.get(combo) ?? [];
    stack.push(me);
    hotkeyOwners.set(combo, stack);
    const mod = combo.startsWith("mod+");
    const key = (mod ? combo.slice(4) : combo).toLowerCase();
    const onKey = (e: KeyboardEvent) => {
      if (hotkeyOwners.get(combo)?.at(-1) !== me || e.key.toLowerCase() !== key) return;
      if (mod ? !(e.metaKey || e.ctrlKey) : e.metaKey || e.ctrlKey || e.altKey) return;
      if (!mod && (e.target as HTMLElement | null)?.closest("input, textarea, select, [contenteditable=true]")) return;
      e.preventDefault();
      latest.current();
    };
    window.addEventListener("keydown", onKey);
    return () => {
      window.removeEventListener("keydown", onKey);
      const s = hotkeyOwners.get(combo) ?? [];
      s.splice(s.indexOf(me), 1);
    };
  }, [combo, latest]);
}

/** Keeps the latest value in a ref, for callbacks read inside timers and animation frames. */
export function useLatest<T>(value: T) {
  const ref = React.useRef(value);
  React.useLayoutEffect(() => {
    ref.current = value;
  });
  return ref;
}

/*
 * Where Notchset overlays (menus, popovers, tooltips) portal to. Unset, document.body, as shadcn's
 * do. Provide an element to keep them inside a scoped theme: a preview, a widget, a shadow root.
 */
export const NotchsetPortalContext = React.createContext<HTMLElement | null>(null);
export function useNotchsetPortal(): HTMLElement | undefined {
  return React.useContext(NotchsetPortalContext) ?? undefined;
}

const subscribeNothing = () => () => {};

/**
 * A scope that turns motion or sound off for everything inside it, popups included. A plain
 * data-motion="off" wrapper can't reach a menu that portals to the body; this one also gives its
 * overlays a portal host carrying the same preferences (inside any outer scope's host), so motionOff
 * and the cues see them there too.
 */
export function NotchsetScope({ motion, sound, children, ...props }: React.ComponentProps<"div"> & { motion?: "off"; sound?: "off" }) {
  const outer = React.useContext(NotchsetPortalContext);
  const [host, setHost] = React.useState<HTMLElement | null>(null);
  const client = React.useSyncExternalStore(subscribeNothing, () => true, () => false);
  return (
    <div data-motion={motion} data-sound={sound} {...props}>
      <NotchsetPortalContext value={host ?? outer}>{children}</NotchsetPortalContext>
      {client && createPortal(<div ref={setHost} data-slot="notchset-scope-host" data-motion={motion} data-sound={sound} />, outer ?? document.body)}
    </div>
  );
}

export { NOTCHSET_ROOT, OWN_SOUND } from "@/lib/beautiful-ui/notchset/root";

// ---------------------------------------------------------------------------------------------
// Parts
// ---------------------------------------------------------------------------------------------

export type NodeState = "off" | "on" | "live" | "signal";

/** The node: a 9×9 ring whose dot blooms on (`on`), blinks (`live`) or turns signal. */
function Node({ state = "off", delay, className, style, ...props }: Omit<React.ComponentProps<"svg">, "children"> & { state?: NodeState; delay?: number }) {
  return (
    <svg
      aria-hidden
      data-slot="indicator"
      data-state={state}
      width="9"
      height="9"
      viewBox="0 0 9 9"
      className={cn(`notchset-node`, className)}
      style={delay ? ({ "--notchset-node-delay": `${delay}ms`, ...style } as React.CSSProperties) : style}
      {...props}
    >
      <circle data-slot="indicator-ring" cx="4.5" cy="4.5" r="3.25" fill="none" strokeWidth="1" />
      <circle data-slot="indicator-dot" cx="4.5" cy="4.5" />
    </svg>
  );
}

/** A small solid round mark (the node where a leader meets a popup, a pointer): SVG, round at every DPR. */
function Dot({ size = 7, className, style }: { size?: number; className?: string; style?: React.CSSProperties }) {
  return (
    <svg aria-hidden width={size} height={size} viewBox={`0 0 ${size} ${size}`} className={cn("pointer-events-none absolute overflow-visible", className)} style={style}>
      <circle cx={size / 2} cy={size / 2} r={size / 2} fill="currentColor" />
    </svg>
  );
}

/** The legend: a mono label above a control, with an optional node (or any trailing reading). */
function Legend({ label, node, children, className, ...props }: React.ComponentProps<"div"> & { label?: React.ReactNode; node?: NodeState }) {
  return (
    <div data-slot="legend" className={cn(`notchset-legend`, className)} {...props}>
      <span data-slot="legend-label">{label}</span>
      {(children != null || node) && (
        <span data-slot="legend-reading" className="flex items-center gap-2">
          {children}
          {node && <Node state={node} />}
        </span>
      )}
    </div>
  );
}

/** A key on its plate: the plate is an offset frame behind the child; `--notchset-plate-color` tints it. */
function Plated({ className, children, ...props }: React.ComponentProps<"span">) {
  return (
    <span data-slot="plated" className={cn("relative inline-flex", className)} {...props}>
      <span aria-hidden data-slot="plate" className={`notchset-plate`} />
      {children}
    </span>
  );
}

/**
 * The success check. Mounted, it traces itself in over --notchset-check (instant under reduced
 * motion); pass `drawn` to drive the trace yourself.
 */
function Check({ drawn, size = 16 }: { drawn?: boolean; size?: number }) {
  return (
    <svg aria-hidden data-slot="check" width={size} height={size} viewBox="0 0 24 24">
      <path
        d="M4 12.5 L9.5 18 L20 6"
        fill="none"
        stroke="currentColor"
        strokeWidth={1.75}
        strokeLinecap="square"
        pathLength={1}
        strokeDasharray={1}
        className={drawn === undefined ? `notchset-check-draw` : undefined}
        style={drawn === undefined ? undefined : { strokeDashoffset: drawn ? 0 : 1, transition: "stroke-dashoffset var(--notchset-check) var(--notchset-ease-travel)" }}
      />
    </svg>
  );
}

/** The scanner: five 1px ticks fading in turn while something works (static, centre lit, when motion is off). */
function Scanner({ height = 12 }: { height?: number }) {
  return (
    <span aria-hidden data-slot="scanner" className={cn(`notchset-scanner`, "inline-flex items-end gap-[2px]")} style={{ height }}>
      {[0.82, 0.66, 1, 0.66, 0.82].map((h, i) => (
        <span key={i} className="w-px bg-current" style={{ height: height * h, animationDelay: `${i * 140 - 700}ms` }} />
      ))}
    </span>
  );
}

// ---------------------------------------------------------------------------------------------
// Glyph flip: each character cycles through glyphs and lands at 110 + i·14ms, left to right
// ---------------------------------------------------------------------------------------------

const GLYPHS = "ABCDEFGHJKLMNPRSTUVWXYZ0123456789#/+=";
const STILL = new Set([" ", "·", "/", ".", ":"]);
const FLIP_CHARS = 24;

export function scramble(text: string, elapsed: number) {
  let out = "";
  for (let i = 0; i < text.length; i++) {
    const ch = text[i]!;
    // Characters past the 24th land with the 24th, so a long label flips as briefly as a short one.
    out += STILL.has(ch) || elapsed >= 110 + Math.min(i, FLIP_CHARS) * 14 ? ch : GLYPHS[(Math.floor(elapsed / 36) * 5 + i * 11) % GLYPHS.length];
  }
  return out;
}

/**
 * The text to show for `text`: when it changes, a few frames of glyphs that land left to right.
 * Runs on requestAnimationFrame only while a flip is active; the settled text is never state. Off
 * under reduced motion, inside data-motion="off" (pass the element) or with `off`.
 */
export function useGlyphFlip(text: string, { off = false, el }: { off?: boolean; el?: React.RefObject<Element | null> } = {}) {
  const [frame, setFrame] = React.useState<{ for: string; shown: string } | null>(null);
  const first = React.useRef(true);
  React.useEffect(() => {
    if (first.current) {
      first.current = false;
      return;
    }
    if (off || motionOff(el?.current)) return;
    let raf = 0;
    const t0 = performance.now();
    const end = 110 + Math.min(text.length, FLIP_CHARS) * 14 + 40;
    const step = (now: number) => {
      const elapsed = now - t0;
      if (elapsed >= end) {
        setFrame(null);
        return;
      }
      setFrame({ for: text, shown: scramble(text, elapsed) });
      raf = requestAnimationFrame(step);
    };
    raf = requestAnimationFrame(step);
    return () => cancelAnimationFrame(raf);
  }, [text, off, el]);
  // Turned off mid-flip, the label shows its text at once (the cancelled frame never lingers).
  return !off && frame && frame.for === text ? frame.shown : text;
}

/** A label that flips when its text changes; screen readers read the final text only. */
function FlipText({ children, off, className, ref: refProp, ...props }: Omit<React.ComponentProps<"span">, "children"> & { children: string; off?: boolean }) {
  const ref = React.useRef<HTMLSpanElement>(null);
  const refs = useComposedRefs<HTMLSpanElement>(refProp, ref);
  const shown = useGlyphFlip(children, { off, el: ref });
  return (
    <span {...props} ref={refs} data-slot="flip-text" className={cn("relative whitespace-nowrap", className)}>
      <span aria-hidden>{shown}</span>
      <span className="sr-only">{children}</span>
    </span>
  );
}

// ---------------------------------------------------------------------------------------------
// Sound: Notchset components announce cues; the page's beautiful-ui-sound layer (opt-in) plays them.
// ---------------------------------------------------------------------------------------------

/** The Notchset cues, in the shared sound layer's names (played in the mechanical voice). */
export const NOTCHSET_CUES = { tap: "tap", latch: "lock", signal: "destructive", confirm: "halt", done: "success", tick: "tick" } as const;
export type NotchsetCue = keyof typeof NOTCHSET_CUES;

export function playCue(el: Element | null, cue: NotchsetCue) {
  if (!el || typeof CustomEvent === "undefined" || el.closest('[data-sound="off"]')) return;
  el.dispatchEvent(new CustomEvent("beautiful-ui:sound", { bubbles: true, detail: { cue: NOTCHSET_CUES[cue] } }));
}

// ---------------------------------------------------------------------------------------------
// Shortcuts: "⌘↵" → "Meta+Enter Control+Enter" (aria-keyshortcuts)
// ---------------------------------------------------------------------------------------------

const KEY_NAMES: Record<string, string> = { "⌘": "Meta", "⌃": "Control", "⌥": "Alt", "⇧": "Shift", "↵": "Enter", "⏎": "Enter", "⎋": "Escape", "⌫": "Backspace", "⇥": "Tab", "␣": "Space" };

export function kbdToShortcut(kbd: string | undefined): string | undefined {
  if (!kbd) return undefined;
  const parts = [...kbd.replace(/\s+/g, "")].map((c) => KEY_NAMES[c] ?? c.toUpperCase());
  if (!parts.length) return undefined;
  const combo = parts.join("+");
  // ⌘ on a Mac is Ctrl elsewhere: announce both.
  return combo.includes("Meta") ? `${combo} ${combo.replace("Meta", "Control")}` : combo;
}

/**
 * Digits that roll: each digit is a 0–9 strip; the ones digit moves first and each digit to its left
 * 40ms later, counting digits only (620ms, a small overshoot). `delay` offsets the whole text. Other
 * characters (",", "$", "%", letters) sit still. Screen readers get the plain text. The one
 * implementation behind RollingNumber and the calendar's RollingLabel.
 */
export function DigitRoll({ text, height, delay = 0, className }: { text: string; height: number; delay?: number; className?: string }) {
  const chars = [...text];
  let k = 0;
  const order = chars.map((_, i) => (/\d/.test(chars[chars.length - 1 - i]!) ? k++ : 0)).reverse();
  return (
    <span className={cn("relative inline-flex flex-none overflow-hidden tabular-nums", className)} style={{ height, lineHeight: `${height}px` }}>
      <span className="sr-only">{text}</span>
      <span aria-hidden className="flex">
        {chars.map((d, i) =>
          /\d/.test(d) ? (
            <span
              key={chars.length - i}
              className="flex flex-col transition-transform duration-[620ms] ease-[cubic-bezier(.34,1.15,.5,1)] motion-reduce:transition-none"
              style={{ transform: `translateY(${-Number(d) * height}px)`, transitionDelay: `${delay + order[i]! * 40}ms` }}
            >
              {Array.from({ length: 10 }, (_, n) => (
                <span key={n} style={{ height }}>
                  {n}
                </span>
              ))}
            </span>
          ) : (
            <span key={`s${chars.length - i}`}>{d}</span>
          ),
        )}
      </span>
    </span>
  );
}

/** A number that rolls (DigitRoll at the readout's own size). `delay` offsets it (rows 60ms apart). */
function RollingNumber({ value, height = 32, delay = 0, className }: { value: string | number; height?: number; delay?: number; className?: string }) {
  return <DigitRoll text={String(value)} height={height} delay={delay} {...(className ? { className } : {})} />;
}

export { Check, Dot, FlipText, Legend, Node, Plated, RollingNumber, Scanner };
```

### lib/beautiful-ui/notchset/root.ts

```tsx
/*
 * Notchset's root attributes, server-safe (no client directive), so server components can spread
 * them too. Every Notchset root (and portalled popup) carries data-notchset (the motion policy's
 * scope), plays its own cues in the mechanical voice, and keeps the page's click layer out.
 */
export const NOTCHSET_ROOT = { "data-notchset": "", "data-sound": "none", "data-sound-voice": "analogue" } as const;

/** On every interactive element: it plays its own cues, so the page's click layer adds no tap. */
export const OWN_SOUND = { "data-sound": "none" } as const;
```

### lib/beautiful-ui/notchset/button-variants.ts

```tsx
import { cva } from "class-variance-authority";

/*
 * Notchset Button's variants, server-safe like shadcn's: call buttonVariants() from a Server Component
 * (links styled as buttons). The interactive Button lives in a client module.
 */

export const buttonVariants = cva(
  "group/button relative isolate inline-flex shrink-0 cursor-pointer items-center justify-center gap-(--b-gap) rounded-none border-0 font-mono font-medium tracking-[0.06em] whitespace-nowrap uppercase outline-none select-none transition-[background-color,color,translate,border-color] duration-[var(--notchset-fade),var(--notchset-fade),var(--notchset-key-up),var(--notchset-fade)] ease-[var(--notchset-ease-fade),var(--notchset-ease-fade),var(--notchset-ease-key-up),var(--notchset-ease-fade)] disabled:cursor-not-allowed disabled:opacity-40 aria-disabled:cursor-not-allowed aria-disabled:opacity-40 aria-busy:cursor-progress [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-(--b-ic) aria-pressed:bg-primary aria-pressed:text-primary-foreground data-[mode=armed]:bg-[var(--notchset-signal-text,var(--destructive))] data-[mode=armed]:text-primary-foreground data-[mode=hold]:translate-x-[2px] data-[mode=hold]:translate-y-[2px] data-[mode=hold]:duration-[var(--notchset-key-down)] data-[mode=hold]:ease-[var(--notchset-ease-key-down)]",
  {
    variants: {
      variant: {
        default: "bg-primary text-primary-foreground hover:bg-[var(--notchset-primary-hover,color-mix(in_oklab,var(--primary)_86%,var(--background)))] active:bg-[var(--notchset-primary-press,var(--primary))] [--b-tick:var(--notchset-tick-on-primary,color-mix(in_oklab,var(--primary-foreground)_34%,transparent))] [--b-kbd:var(--notchset-kbd-on-primary,color-mix(in_oklab,var(--primary-foreground)_45%,transparent))]",
        destructive:
          "bg-[var(--notchset-signal,var(--destructive))] text-[color:var(--notchset-on-signal,white)] hover:bg-[var(--notchset-signal-hover,var(--destructive))] active:bg-[var(--notchset-signal-press,var(--destructive))] [--b-tick:var(--notchset-tick-on-primary,color-mix(in_oklab,white_34%,transparent))] [--b-kbd:var(--notchset-kbd-on-signal,color-mix(in_oklab,black_40%,transparent))] [--notchset-focus-color:var(--notchset-signal-text,var(--destructive))]",
        outline: "border border-solid border-foreground bg-transparent text-foreground hover:bg-accent active:bg-[var(--notchset-tint-press,var(--accent))]",
        secondary: "bg-secondary text-secondary-foreground hover:bg-[var(--notchset-secondary-hover,var(--secondary))] active:bg-[var(--notchset-secondary-press,var(--secondary))]",
        signal:
          "border border-solid border-[var(--notchset-signal-text,var(--destructive))] bg-background text-[color:var(--notchset-signal-text,var(--destructive))] hover:bg-[var(--notchset-tint,color-mix(in_oklab,var(--destructive)_12%,var(--background)))] [--notchset-button-fill:color-mix(in_oklab,var(--notchset-signal,var(--destructive))_26%,var(--background))] [--notchset-button-meter:var(--notchset-signal,var(--destructive))] [--notchset-focus-color:var(--notchset-signal-text,var(--destructive))]",
        ghost: "bg-transparent text-foreground hover:bg-accent active:bg-[var(--notchset-tint-press,var(--accent))]",
        link: "h-auto min-w-0 justify-start bg-transparent px-0.5 pt-[3px] pb-1.5 text-foreground active:text-[var(--notchset-signal-text,var(--destructive))]",
        plate: "bg-primary text-primary-foreground hover:bg-[var(--notchset-primary-hover,color-mix(in_oklab,var(--primary)_86%,var(--background)))] active:translate-x-[2px] active:translate-y-[2px] active:duration-[var(--notchset-key-down)] active:ease-[var(--notchset-ease-key-down)]",
      },
      size: {
        // The market's heights (shadcn, and Kobra on it): XS 24, S 28, default 32, L 36. Labels are mono caps,
        // which read larger than the 14px sans those libraries use, so 12px (13px on L) matches them optically.
        // Same size names as shadcn, so it stays a drop-in. At least 44px tall on touch screens.
        default: "h-8 min-w-8 px-3 text-[12px] [--b-gap:8px] [--b-ic:16px] [--b-kh:18px] [--b-kfs:10px] pointer-coarse:min-h-11",
        xs: "h-6 min-w-6 px-2 text-[12px] [--b-gap:6px] [--b-ic:14px] [--b-kh:14px] [--b-kfs:10px] pointer-coarse:min-h-11",
        sm: "h-7 min-w-7 px-2.5 text-[12px] [--b-gap:7px] [--b-ic:16px] [--b-kh:16px] [--b-kfs:10px] pointer-coarse:min-h-11",
        lg: "h-9 min-w-9 px-4 text-[13px] [--b-gap:8px] [--b-ic:16px] [--b-kh:20px] [--b-kfs:10px] pointer-coarse:min-h-11",
        icon: "size-8 [--b-ic:16px]",
        "icon-xs": "size-6 [--b-ic:14px]",
        "icon-sm": "size-7 [--b-ic:16px]",
        "icon-lg": "size-9 [--b-ic:16px]",
      },
    },
    // The link's drawn rule lives in the Notchset foundation (a system class, kept out of the utilities).
    // The shared press (a 1px content dip) on every variant but plate, which moves whole onto its plate.
    compoundVariants: [
      { variant: "link", class: `notchset-link` },
      { variant: ["default", "destructive", "outline", "secondary", "signal", "ghost", "link"], class: `notchset-press` },
    ],
    defaultVariants: { variant: "default", size: "default" },
  },
);

export type ButtonVariant = NonNullable<Parameters<typeof buttonVariants>[0]>["variant"];
export type ButtonSize = NonNullable<Parameters<typeof buttonVariants>[0]>["size"];
```

### lib/beautiful-ui/notchset/field-classes.ts

```tsx
import { cn } from "@/lib/utils";

/*
 * Notchset field classes, server-safe (no client directive), so the bare Input and Textarea keep
 * their look in server components. The focus is a 2px ink trace drawn along the bottom edge from the
 * left, never a ring; invalid keeps a signal trace drawn; forced colors get a system outline.
 */

/** The focus trace and states, as utilities on the element itself (no wrapper needed). */
const TRACE =
  "bg-no-repeat [background-image:linear-gradient(var(--foreground),var(--foreground))] [background-position:left_bottom] [background-size:0_2px] focus:[background-size:100%_2px] aria-invalid:[background-image:linear-gradient(var(--notchset-signal,var(--destructive)),var(--notchset-signal,var(--destructive)))] aria-invalid:[background-size:100%_2px] forced-colors:focus:outline forced-colors:focus:outline-2 forced-colors:focus:outline-offset-2 forced-colors:focus:outline-[Highlight] transition-[border-color,background-size] duration-[140ms,200ms] ease-[linear,var(--notchset-ease-travel)] focus:duration-[140ms,300ms]";

export const inputClass = cn(
  "flex h-10 w-full min-w-0 border border-solid border-[var(--notchset-control-edge,var(--input))] bg-background px-3 py-0 font-mono text-[13px] tracking-[0.01em] text-foreground outline-none",
  "caret-[var(--notchset-signal,var(--destructive))] selection:bg-[var(--notchset-tint,color-mix(in_oklab,var(--destructive)_18%,transparent))] placeholder:text-muted-foreground",
  "hover:border-foreground focus:border-foreground aria-invalid:border-[var(--notchset-signal-text,var(--destructive))]",
  "disabled:cursor-not-allowed disabled:border-[var(--notchset-rule,var(--border))] disabled:opacity-40",
  "file:inline-flex file:h-full file:border-0 file:bg-transparent file:font-mono file:text-[11px] file:font-medium file:tracking-[0.07em] file:text-foreground file:uppercase",
  "pointer-coarse:h-11",
  TRACE,
);

export const textareaClass = cn(
  "flex field-sizing-content min-h-24 w-full border border-solid border-[var(--notchset-control-edge,var(--input))] bg-background px-3 pt-[11px] pb-1.5 font-sans text-sm leading-[1.5] text-foreground outline-none",
  "caret-[var(--notchset-signal,var(--destructive))] selection:bg-[var(--notchset-tint,color-mix(in_oklab,var(--destructive)_18%,transparent))] placeholder:text-muted-foreground",
  "hover:border-foreground focus:border-foreground aria-invalid:border-[var(--notchset-signal-text,var(--destructive))]",
  "disabled:cursor-not-allowed disabled:border-[var(--notchset-rule,var(--border))] disabled:opacity-40",
  TRACE,
);
```

The notchset foundation (the tokens listed above, keyframes and motion levels) installs once with the first component; its CSS is public at https://beautiful-ui.dev/r/notchset-foundation.json.