07Fading attempt history — every new attempt added lowers the opacity value of older entries in the list

<main class="stage">
<div class="ahf is-demo" id="ahf">
  <button class="ahf__btn" id="ahfBtn" type="button">Add login attempt</button>
  <ul class="ahf__list" id="ahfList"></ul>
</div>
</main>

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

// 계산 겹: i번째(0=최신) 기록의 불투명도 = max(최소, 1 − i×STEP) — index.html 참조
@include stage($stage-orange);

.ahf {
  width: 100%;
  max-width: 300px;
  display: grid;
  gap: $sp-3;
  justify-items: center;
}

.ahf__btn {
  border: 0;
  border-radius: $r-control;
  padding: $sp-2 $sp-4;
  background: $stage-ink;
  color: $subject-cream;
  font: 700 13px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  cursor: pointer;
  transition: transform $dur-instant $ease-out;

  &:active { transform: scale(.96); }
}

.ahf__list {
  width: 100%;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: $sp-2;
}

.ahf__row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: $sp-2 $sp-3;
  border-radius: $r-sm;
  background: $subject-cream;
  font: 600 12px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  animation: ahf-in $dur-quick $ease-out backwards;
}

@keyframes ahf-in {
  from { transform: translateY(-8px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

.ahf__time { color: rgba($stage-ink, .6); }

.ahf__result { color: $stage-ink; }

.ahf__row--fail .ahf__result { color: $error; }
.ahf__row--ok .ahf__result { color: $subject-blue-deep; }

@media (max-width: 340px) {
  .ahf { max-width: 220px; }
  .ahf__row { font-size: 11px; padding: $sp-2 $sp-2; }
}

@media (prefers-reduced-motion: reduce) {
  .ahf__btn { transition: none; }
  .ahf__row { animation: none; }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ff4d1f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.ahf {
  width: 100%;
  max-width: 300px;
  display: grid;
  gap: 12px;
  justify-items: center;
}

.ahf__btn {
  border: 0;
  border-radius: 12px;
  padding: 8px 16px;
  background: #17141a;
  color: #fff7e6;
  font: 700 13px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  cursor: pointer;
  transition: transform 140ms ease-out;
}
.ahf__btn:active {
  transform: scale(0.96);
}

.ahf__list {
  width: 100%;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.ahf__row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  border-radius: 8px;
  background: #fff7e6;
  font: 600 12px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  animation: ahf-in 220ms ease-out backwards;
}

@keyframes ahf-in {
  from {
    transform: translateY(-8px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}
.ahf__time {
  color: rgba(23, 20, 26, 0.6);
}

.ahf__result {
  color: #17141a;
}

.ahf__row--fail .ahf__result {
  color: #c2361a;
}

.ahf__row--ok .ahf__result {
  color: #0a4fe8;
}

@media (max-width: 340px) {
  .ahf {
    max-width: 220px;
  }
  .ahf__row {
    font-size: 11px;
    padding: 8px 8px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .ahf__btn {
    transition: none;
  }
  .ahf__row {
    animation: none;
  }
}

(function () {
  var root = document.getElementById('ahf');
  var btn = document.getElementById('ahfBtn');
  var list = document.getElementById('ahfList');

  // 상수: 화면에 보이는 최대 기록 수 · 기록 하나마다 낮아지는 투명도 폭 · 최소 투명도
  var MAX_ENTRIES = 5;
  var OPACITY_STEP = 0.18;
  var MIN_OPACITY = 0.16;

  var SEQ = ['Fail', 'Fail', 'Success', 'Fail', 'Fail', 'Fail', 'Success', 'Fail'];
  var seqIdx = 0;
  var entries = []; // 최신이 index 0

  function fmtTime(n) {
    var m = String(10 + n % 50).padStart(2, '0');
    return '10:' + m;
  }

  // 계산 겹: i번째(0=최신) 항목의 불투명도 = max(최소, 1 − i×STEP)
  function render() {
    list.innerHTML = '';
    for (var i = 0; i < entries.length; i++) {
      var e = entries[i];
      var op = Math.max(MIN_OPACITY, 1 - i * OPACITY_STEP);
      var li = document.createElement('li');
      li.className = 'ahf__row' + (e.result === 'Fail' ? ' ahf__row--fail' : ' ahf__row--ok');
      li.style.opacity = op.toFixed(2);
      li.innerHTML = '<span class="ahf__time">' + e.time + '</span>' +
        '<span class="ahf__result">' + e.result + '</span>';
      list.appendChild(li);
    }
  }

  function addEntry() {
    var result = SEQ[seqIdx % SEQ.length];
    seqIdx += 1;
    entries.unshift({ result: result, time: fmtTime(seqIdx) });
    if (entries.length > MAX_ENTRIES) entries.length = MAX_ENTRIES;
    render();
  }

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

  var autoTimer = null;
  function stopAutoplay() { if (autoTimer) { clearInterval(autoTimer); autoTimer = null; } }
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  if (!reduce) { autoTimer = setInterval(addEntry, 340); }
})();

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

type Box<T> = { current: T };
type Entry = { result: string; time: string };

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

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

    // 상수: 화면에 보이는 최대 기록 수 · 기록 하나마다 낮아지는 투명도 폭 · 최소 투명도
    const MAX_ENTRIES = 5;
    const OPACITY_STEP = 0.18;
    const MIN_OPACITY = 0.16;

    const SEQ = ["실패", "실패", "성공", "실패", "실패", "실패", "성공", "실패"];
    let seqIdx = 0;
    let entries: Entry[] = [];

    function fmtTime(n: number) {
      const m = String(10 + (n % 50)).padStart(2, "0");
      return "10:" + m;
    }

    // 계산 겹: i번째(0=최신) 항목의 불투명도 = max(최소, 1 − i×STEP)
    function render() {
      list!.innerHTML = "";
      for (let i = 0; i < entries.length; i++) {
        const e = entries[i];
        const op = Math.max(MIN_OPACITY, 1 - i * OPACITY_STEP);
        const li = document.createElement("li");
        li.className = styles.row + " " + (e.result === "실패" ? styles["row--fail"] : styles["row--ok"]);
        li.style.opacity = op.toFixed(2);
        li.innerHTML =
          '<span class="' + styles.time + '">' + e.time + "</span>" +
          '<span class="' + styles.result + '">' + e.result + "</span>";
        list!.appendChild(li);
      }
    }

    function addEntry() {
      const result = SEQ[seqIdx % SEQ.length];
      seqIdx += 1;
      entries.unshift({ result, time: fmtTime(seqIdx) });
      if (entries.length > MAX_ENTRIES) entries.length = MAX_ENTRIES;
      render();
    }

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

    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(addEntry, 340); }

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

  return (
    <div ref={rootRef} className={`${styles.stage} ${styles.ahf} ${styles["is-demo"]}`}>
      <button className={styles.btn} type="button">로그인 시도 추가</button>
      <ul className={styles.list} />
    </div>
  );
}