01Three-dot bounce — a basic indicator staggered by index

<main class="stage">
<section class="panel">
  <div class="row">
    <span class="avatar" aria-hidden="true"></span>
    <div class="bubble" role="status" aria-live="polite" aria-label="Typing">
      <span class="dot" data-i="0"></span>
      <span class="dot" data-i="1"></span>
      <span class="dot" data-i="2"></span>
    </div>
  </div>
</section>
</main>

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

@include stage($stage-ink);

.panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: $sp-4;
}

.row {
  display: flex;
  align-items: center;
  gap: $sp-3;
}

.avatar {
  width: 32px;
  height: 32px;
  border-radius: $r-pill;
  background: $subject-blue;
  flex: none;
}

.bubble {
  display: inline-flex;
  align-items: center;
  gap: $sp-2;
  padding: $sp-3 $sp-4;
  border-radius: $r-card;
  background: $subject-cream;
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: $subject-ink;
  animation-name: dotBounce;
  animation-duration: $dur-loop;
  animation-timing-function: $ease-spring;
  animation-iteration-count: infinite;
  animation-delay: var(--delay, 0ms);
}

@keyframes dotBounce {
  0%, 60%, 100% { transform: translateY(0); opacity: .5; }
  30% { transform: translateY(-6px); opacity: 1; }
}

@media (max-width: 340px) {
  .bubble { padding: $sp-2 $sp-3; gap: $sp-1; }
  .avatar { width: 26px; height: 26px; }
}

@media (prefers-reduced-motion: reduce) {
  .dot { animation: none; opacity: .8; transform: none; }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.avatar {
  width: 32px;
  height: 32px;
  border-radius: 999px;
  background: #2f6df6;
  flex: none;
}

.bubble {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border-radius: 16px;
  background: #fff7e6;
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #17141a;
  animation-name: dotBounce;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 0.8, 0.2, 1);
  animation-iteration-count: infinite;
  animation-delay: var(--delay, 0ms);
}

@keyframes dotBounce {
  0%, 60%, 100% {
    transform: translateY(0);
    opacity: 0.5;
  }
  30% {
    transform: translateY(-6px);
    opacity: 1;
  }
}
@media (max-width: 340px) {
  .bubble {
    padding: 8px 12px;
    gap: 4px;
  }
  .avatar {
    width: 26px;
    height: 26px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .dot {
    animation: none;
    opacity: 0.8;
    transform: none;
  }
}

// 점 3개 바운스 — 각 점이 튀어 오르는 시작 시점을 점의 순서(index) 값에 간격을 곱해 다시 구한다.
// 계산 겹: 인덱스 × 간격(ms) → animation-delay 재계산(setProperty). 자동 재생만, 실사용자 리스너 없음.
(function () {
  var DOT_STAGGER_MS = 120;
  var dots = document.querySelectorAll('.dot');
  if (!dots.length) return;
  dots.forEach(function (dot) {
    var i = Number(dot.dataset.i || 0);
    dot.style.setProperty('--delay', (i * DOT_STAGGER_MS) + 'ms');
  });
})();

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

// 점 3개 바운스 — 각 점이 튀어 오르는 시작 시점을 점의 순서(index) 값에 간격을 곱해 다시 구한다.
// 계산 겹: 인덱스 × 간격(ms) → animation-delay 재계산(setProperty). 자동 재생만, 실사용자 리스너 없음.
const DOT_STAGGER_MS = 120;

export default function TypingDotBounceBasic() {
  const dot0Ref = useRef<HTMLSpanElement>(null);
  const dot1Ref = useRef<HTMLSpanElement>(null);
  const dot2Ref = useRef<HTMLSpanElement>(null);

  useEffect(() => {
    const dots = [dot0Ref.current, dot1Ref.current, dot2Ref.current];
    dots.forEach((dot, i) => {
      if (!dot) return;
      dot.style.setProperty("--delay", i * DOT_STAGGER_MS + "ms");
    });
  }, []);

  return (
    <div className={styles.stage}>
      <section className={styles.panel}>
        <div className={styles.row}>
          <span className={styles.avatar} aria-hidden="true" />
          <div className={styles.bubble} role="status" aria-live="polite" aria-label="입력 중">
            <span ref={dot0Ref} className={styles.dot} />
            <span ref={dot1Ref} className={styles.dot} />
            <span ref={dot2Ref} className={styles.dot} />
          </div>
        </div>
      </section>
    </div>
  );
}