04マスク値切替 — マスクの値がオンになると先頭の数桁を残し残りの桁の値が記号値に変わる方式

<main class="stage">
<div class="cm is-demo" id="cm">
  <div class="cm__row" id="cmRow"></div>
  <button type="button" class="cm__toggle" id="cmToggle" aria-pressed="false">マスク値切替</button>
</div>
</main>

@use "../../../../site/static/demo-tokens" as *;

// 계산 겹: 가림 값 전환이 자릿수 값 순서대로 STAGGER_MS 씩 늦게 퍼진다(index.html --i, transition-delay).
@include stage($stage-paper);

.cm {
  width: 100%;
  max-width: 320px;
  display: grid;
  gap: $sp-5;
  justify-items: center;
}

.cm__row {
  display: flex;
  align-items: center;
  background: $subject-ink;
  border-radius: $r-control;
  padding: $sp-4;
  box-sizing: border-box;
  width: 100%;
}

.cm__group {
  position: relative;
  width: 13px;
  height: 20px;
  margin-right: 0;

  &--gap { margin-left: $sp-2; }
}

.cm__digit,
.cm__mask {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-weight: 600;
  font-size: 16px;
  color: $subject-cream;
  transition: transform $dur-quick $ease-spring, opacity $dur-quick $ease-out;
  transition-delay: calc(var(--i, 0) * 45ms);
}

.cm__digit--fixed { position: static; transition: none; }

.cm__mask {
  opacity: 0;
  transform: scale(.4);
}

.cm--masked {
  .cm__digit:not(.cm__digit--fixed) { opacity: 0; transform: scale(.4); }
  .cm__mask { opacity: 1; transform: scale(1); }
}

.cm__toggle {
  border: 0;
  border-radius: $r-pill;
  padding: $sp-2 $sp-5;
  background: $subject-ink;
  color: $subject-cream;
  font-weight: 700;
  font-size: 13px;
  cursor: pointer;
  transition: transform $dur-instant $ease-out;

  &:active { transform: scale(.95); }
  &:focus-visible { outline: 2px solid $subject-blue-deep; outline-offset: 2px; }
}

@media (max-width: 340px) {
  .cm__row { padding: $sp-3; }
  .cm__group { width: 11px; }
  .cm__digit, .cm__mask { font-size: 14px; }
}

@media (prefers-reduced-motion: reduce) {
  .cm__digit, .cm__mask { transition: none; transition-delay: 0ms; }
  .cm__toggle { transition: none; }
}

html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffffff;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.cm {
  width: 100%;
  max-width: 320px;
  display: grid;
  gap: 20px;
  justify-items: center;
}

.cm__row {
  display: flex;
  align-items: center;
  background: #17141a;
  border-radius: 12px;
  padding: 16px;
  box-sizing: border-box;
  width: 100%;
}

.cm__group {
  position: relative;
  width: 13px;
  height: 20px;
  margin-right: 0;
}
.cm__group--gap {
  margin-left: 8px;
}

.cm__digit,
.cm__mask {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-weight: 600;
  font-size: 16px;
  color: #fff7e6;
  transition: transform 220ms cubic-bezier(0.2, 0.8, 0.2, 1), opacity 220ms ease-out;
  transition-delay: calc(var(--i, 0) * 45ms);
}

.cm__digit--fixed {
  position: static;
  transition: none;
}

.cm__mask {
  opacity: 0;
  transform: scale(0.4);
}

.cm--masked .cm__digit:not(.cm__digit--fixed) {
  opacity: 0;
  transform: scale(0.4);
}
.cm--masked .cm__mask {
  opacity: 1;
  transform: scale(1);
}

.cm__toggle {
  border: 0;
  border-radius: 999px;
  padding: 8px 20px;
  background: #17141a;
  color: #fff7e6;
  font-weight: 700;
  font-size: 13px;
  cursor: pointer;
  transition: transform 140ms ease-out;
}
.cm__toggle:active {
  transform: scale(0.95);
}
.cm__toggle:focus-visible {
  outline: 2px solid #0a4fe8;
  outline-offset: 2px;
}

@media (max-width: 340px) {
  .cm__row {
    padding: 12px;
  }
  .cm__group {
    width: 11px;
  }
  .cm__digit, .cm__mask {
    font-size: 14px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .cm__digit, .cm__mask {
    transition: none;
    transition-delay: 0ms;
  }
  .cm__toggle {
    transition: none;
  }
}

(function () {
  var root = document.getElementById('cm');
  var row = document.getElementById('cmRow');
  var btn = document.getElementById('cmToggle');
  var DIGITS = '9999999999999995';
  var KEEP = 4; // 앞의 몇 자리 값은 항상 그대로
  var STAGGER_MS = 45; // 계산 겹: 자릿수 값마다 이만큼씩 늦게 전환된다

  var cells = [];
  DIGITS.split('').forEach(function (ch, i) {
    var group = document.createElement('span');
    group.className = 'cm__group';
    if (i > 0 && i % 4 === 0) group.classList.add('cm__group--gap');
    if (i < KEEP) {
      group.innerHTML = '<span class="cm__digit cm__digit--fixed">' + ch + '</span>';
    } else {
      var idx = i - KEEP;
      group.style.setProperty('--i', idx);
      group.innerHTML =
        '<span class="cm__digit">' + ch + '</span>' +
        '<span class="cm__mask">•</span>';
      cells.push(group);
    }
    row.appendChild(group);
  });

  var masked = false;
  function paint() {
    root.classList.toggle('cm--masked', masked);
    btn.setAttribute('aria-pressed', String(masked));
  }

  function toggle() {
    masked = !masked;
    paint();
  }

  btn.addEventListener('click', function () {
    root.classList.remove('is-demo');
    stopAutoplay();
    toggle();
  });

  var autoTimer = null;
  function stopAutoplay() { if (autoTimer) { clearInterval(autoTimer); autoTimer = null; } }
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  if (!reduce) { autoTimer = setInterval(toggle, 1500); }
  else { masked = true; paint(); }
})();

import { useEffect, useRef } from "react";
import type { CSSProperties } from "react";
import styles from "./MaskToggleReveal.module.scss";

type Box<T> = { current: T };

const DIGITS = "9999999999999995";
const KEEP = 4; // 앞의 몇 자리 값은 항상 그대로
const STAGGER_MS = 45; // 계산 겹: 자릿수 값마다 이만큼씩 늦게 전환된다

export default function MaskToggleReveal() {
  const rootRef = useRef(null) as unknown as Box<HTMLDivElement | null>;

  useEffect(() => {
    const root = rootRef.current;
    if (!root) return;
    const btn = root.querySelector(`.${styles.toggle}`) as HTMLButtonElement | null;
    if (!btn) return;

    let masked = false;
    function paint() {
      root!.classList.toggle(styles["root--masked"], masked);
      btn!.setAttribute("aria-pressed", String(masked));
    }
    function toggle() { masked = !masked; paint(); }

    function onClick() {
      root!.classList.remove(styles["is-demo"]);
      stopAutoplay();
      toggle();
    }
    btn.addEventListener("click", onClick);

    let autoTimer: number | null = null;
    function stopAutoplay() {
      if (autoTimer !== null) { window.clearInterval(autoTimer); autoTimer = null; }
    }
    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
    if (!reduce) { autoTimer = window.setInterval(toggle, 1500); }
    else { masked = true; paint(); }

    return () => {
      stopAutoplay();
      btn.removeEventListener("click", onClick);
    };
  }, []);

  const cells = DIGITS.split("").map((ch, i) => ({
    ch,
    gapBefore: i > 0 && i % 4 === 0,
    fixed: i < KEEP,
    idx: i - KEEP,
  }));

  return (
    <div ref={rootRef} className={`${styles.stage} ${styles.cm} ${styles["is-demo"]}`}>
      <div className={styles.row}>
        {cells.map((c, i) => (
          <span key={i} className={`${styles.group} ${c.gapBefore ? styles["group--gap"] : ""}`}>
            {c.fixed ? (
              <span className={`${styles.digit} ${styles["digit--fixed"]}`}>{c.ch}</span>
            ) : (
              <>
                <span className={styles.digit} style={{ transitionDelay: `${c.idx * STAGGER_MS}ms` } as CSSProperties}>{c.ch}</span>
                <span className={styles.mask} style={{ transitionDelay: `${c.idx * STAGGER_MS}ms` } as CSSProperties}>•</span>
              </>
            )}
          </span>
        ))}
      </div>
      <button type="button" className={styles.toggle} aria-pressed="false">가림 값 전환</button>
    </div>
  );
}