02Character-class count fill — the strength value is set by how many distinct character-type values are mixed into the input

<main class="stage">
<div class="cc is-demo" id="cc">
  <label class="cc__field">
    <input class="cc__input" id="ccInput" type="text" autocomplete="off" spellcheck="false" value="">
  </label>
  <div class="cc__badges">
    <div class="cc__badge" id="ccB0"><span>a-z</span></div>
    <div class="cc__badge" id="ccB1"><span>A-Z</span></div>
    <div class="cc__badge" id="ccB2"><span>0-9</span></div>
    <div class="cc__badge" id="ccB3"><span>#%!</span></div>
  </div>
  <div class="cc__track"><div class="cc__fill" id="ccFill"></div></div>
  <div class="cc__label" id="ccLabel">Char types 0/4</div>
</div>
</main>

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

// 계산 겹: 4개 문자 종류 정규식을 입력 값에 검사해 참인 개수를 세고, 그 개수만큼
// 배지가 중심에서 커지며(scale) 켜지고 막대 채움 비율도 같은 개수/4 로 맞춘다.
@include stage($stage-yellow);

.cc {
  width: 100%;
  max-width: 320px;
  display: grid;
  gap: $sp-3;
}

.cc__field { display: block; }

.cc__input {
  width: 100%;
  box-sizing: border-box;
  padding: $sp-3 $sp-4;
  border-radius: $r-control;
  border: 0;
  background: rgba($stage-ink, .08);
  color: $stage-ink;
  font: 500 16px/1.3 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  letter-spacing: .04em;
  -webkit-text-security: disc;

  &:focus { outline: 2px solid $stage-ink; outline-offset: 2px; }
}

.cc__badges {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: $sp-2;
}

.cc__badge {
  height: 32px;
  border-radius: $r-sm;
  background: rgba($stage-ink, .08);
  display: grid;
  place-items: center;
  transform: scale(.86);
  transform-origin: center; // 스스로 완결한 배지가 중심에서 커진다
  transition: transform $dur-quick $ease-spring, background-color $dur-quick $ease-out;

  span {
    font: 700 12px/1 "Space Mono", monospace;
    color: rgba($stage-ink, .55);
    transition: color $dur-quick $ease-out;
  }

  &--on {
    background: $stage-ink;
    transform: scale(1);
    span { color: $stage-paper; }
  }
}

.cc__track {
  position: relative;
  height: $sp-3;
  border-radius: $r-sm;
  background: rgba($stage-ink, .1);
  overflow: hidden;
}

.cc__fill {
  position: absolute;
  inset: 0;
  border-radius: $r-sm;
  background: $stage-ink;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform $dur-base $ease-out;
}

.cc__label {
  font: 600 13px/1.2 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: $stage-ink;
}

@media (max-width: 340px) {
  .cc { max-width: 260px; }
  .cc__input { padding: $sp-2 $sp-3; font-size: 14px; }
  .cc__badge { height: 28px; }
  .cc__badge span { font-size: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  .cc__badge, .cc__fill { transition: none; }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffd23f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.cc {
  width: 100%;
  max-width: 320px;
  display: grid;
  gap: 12px;
}

.cc__field {
  display: block;
}

.cc__input {
  width: 100%;
  box-sizing: border-box;
  padding: 12px 16px;
  border-radius: 12px;
  border: 0;
  background: rgba(23, 20, 26, 0.08);
  color: #17141a;
  font: 500 16px/1.3 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  letter-spacing: 0.04em;
  -webkit-text-security: disc;
}
.cc__input:focus {
  outline: 2px solid #17141a;
  outline-offset: 2px;
}

.cc__badges {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.cc__badge {
  height: 32px;
  border-radius: 8px;
  background: rgba(23, 20, 26, 0.08);
  display: grid;
  place-items: center;
  transform: scale(0.86);
  transform-origin: center;
  transition: transform 220ms cubic-bezier(0.2, 0.8, 0.2, 1), background-color 220ms ease-out;
}
.cc__badge span {
  font: 700 12px/1 "Space Mono", monospace;
  color: rgba(23, 20, 26, 0.55);
  transition: color 220ms ease-out;
}
.cc__badge--on {
  background: #17141a;
  transform: scale(1);
}
.cc__badge--on span {
  color: #ffffff;
}

.cc__track {
  position: relative;
  height: 12px;
  border-radius: 8px;
  background: rgba(23, 20, 26, 0.1);
  overflow: hidden;
}

.cc__fill {
  position: absolute;
  inset: 0;
  border-radius: 8px;
  background: #17141a;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 300ms ease-out;
}

.cc__label {
  font: 600 13px/1.2 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: #17141a;
}

@media (max-width: 340px) {
  .cc {
    max-width: 260px;
  }
  .cc__input {
    padding: 8px 12px;
    font-size: 14px;
  }
  .cc__badge {
    height: 28px;
  }
  .cc__badge span {
    font-size: 10px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .cc__badge, .cc__fill {
    transition: none;
  }
}

(function () {
  var root = document.getElementById('cc');
  var input = document.getElementById('ccInput');
  var fill = document.getElementById('ccFill');
  var label = document.getElementById('ccLabel');
  var badges = [document.getElementById('ccB0'), document.getElementById('ccB1'), document.getElementById('ccB2'), document.getElementById('ccB3')];

  // 계산 겹: 입력 값을 4개 Char types 정규식으로 각각 검사해 참인 개수를 센다.
  var CLASSES = [/[a-z]/, /[A-Z]/, /[0-9]/, /[^A-Za-z0-9]/];

  function countClasses(value) {
    var n = 0;
    for (var i = 0; i < CLASSES.length; i++) {
      var hit = CLASSES[i].test(value);
      badges[i].classList.toggle('cc__badge--on', hit);
      if (hit) n++;
    }
    return n;
  }

  function paint(value) {
    var n = countClasses(value);
    fill.style.transform = 'scaleX(' + (n / CLASSES.length) + ')';
    label.textContent = 'Char types ' + n + '/4';
  }

  input.addEventListener('input', function () {
    root.classList.remove('is-demo');
    stopAutoplay();
    paint(input.value);
  });

  paint(input.value);

  // 자동 루프: 시드 고정 문자열 배열로 문자 종류를 하나씩 늘렸다 줄인다.
  var SEQ = ['', 'abc', 'abcABC', 'abcABC123', 'abcABC123!@#', 'abcABC123', 'abcABC', 'abc', ''];
  var si = 0;
  var autoTimer = null;
  function autoTick() { input.value = SEQ[si]; paint(SEQ[si]); si = (si + 1) % SEQ.length; }
  function stopAutoplay() { if (autoTimer) { clearInterval(autoTimer); autoTimer = null; } }
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  if (!reduce) { autoTimer = setInterval(autoTick, 340); autoTick(); }
})();

import { useEffect, useRef } from "react";
import styles from "./CharclassFill.module.scss";

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

const CLASSES = [/[a-z]/, /[A-Z]/, /[0-9]/, /[^A-Za-z0-9]/];
const LABELS = ["a-z", "A-Z", "0-9", "#%!"];

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

  useEffect(() => {
    const root = rootRef.current;
    if (!root) return;
    const input = root.querySelector(`.${styles.input}`) as HTMLInputElement | null;
    const fill = root.querySelector(`.${styles.fill}`) as HTMLElement | null;
    const label = root.querySelector(`.${styles.label}`) as HTMLElement | null;
    const badges = Array.prototype.slice.call(
      root.querySelectorAll(`.${styles["cc__badge"]}`)
    ) as HTMLElement[];
    if (!input || !fill || !label) return;

    // 계산 겹: 입력 값을 4개 문자 종류 정규식으로 각각 검사해 참인 개수를 센다.
    function countClasses(value: string) {
      let n = 0;
      for (let i = 0; i < CLASSES.length; i++) {
        const hit = CLASSES[i].test(value);
        badges[i].classList.toggle(styles["cc__badge--on"], hit);
        if (hit) n++;
      }
      return n;
    }

    function paint(value: string) {
      const n = countClasses(value);
      fill!.style.transform = "scaleX(" + (n / CLASSES.length) + ")";
      label!.textContent = "문자 종류 " + n + "/4";
    }

    function onInput() {
      root!.classList.remove(styles["is-demo"]);
      stopAutoplay();
      paint(input!.value);
    }
    input.addEventListener("input", onInput);
    paint(input.value);

    // 자동 루프: 시드 고정 문자열 배열로 문자 종류를 하나씩 늘렸다 줄인다.
    const SEQ = ["", "abc", "abcABC", "abcABC123", "abcABC123!@#", "abcABC123", "abcABC", "abc", ""];
    let si = 0;
    let autoTimer: number | null = null;
    function autoTick() { input!.value = SEQ[si]; paint(SEQ[si]); si = (si + 1) % SEQ.length; }
    function stopAutoplay() { if (autoTimer !== null) { window.clearInterval(autoTimer); autoTimer = null; } }
    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
    if (!reduce) { autoTimer = window.setInterval(autoTick, 340); autoTick(); }

    return () => {
      stopAutoplay();
      input.removeEventListener("input", onInput);
    };
  }, []);

  return (
    <div ref={rootRef} className={`${styles.stage} ${styles.cc} ${styles["is-demo"]}`}>
      <label className={styles.field}>
        <input className={styles.input} type="text" autoComplete="off" spellCheck={false} defaultValue="" />
      </label>
      <div className={styles.badges}>
        {LABELS.map((l) => (
          <div key={l} className={styles["cc__badge"]}>
            <span>{l}</span>
          </div>
        ))}
      </div>
      <div className={styles.track}><div className={styles.fill} /></div>
      <div className={styles.label}>문자 종류 0/4</div>
    </div>
  );
}