09날짜·숫자 형식이 언어마다 다를 때

<main class="stage is-demo">
  <div class="flipwrap">
    <div class="flip">
      <div class="face face--ko"><span class="face__tag">ko</span><span class="face__date">2026. 9. 11.</span></div>
      <div class="face face--en"><span class="face__tag">en</span><span class="face__date">Sep 11, 2026</span></div>
      <div class="face face--ja"><span class="face__tag">ja</span><span class="face__date">2026/09/11</span></div>
    </div>
    <p class="langs"><span class="langs__item" style="--i:0">ko</span><span class="langs__item" style="--i:1">en</span><span class="langs__item" style="--i:2">ja</span></p>
  </div>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-loop;      // 2s — 세 서식 한 바퀴
$easing: $ease-out;
$color: $subject-cream;    // 플립 카드

@include stage($stage-ink);

.flipwrap {
  display: grid;
  justify-items: center;
  row-gap: $sp-3;
  perspective: 640px;
}

.flip {
  position: relative;
  width: min(250px, 84vw);
  height: clamp(84px, 30vw, 118px);
  transform-style: preserve-3d;
}

.face {
  position: absolute;
  inset: 0;
  border-radius: $r-card;
  background: $color;
  box-shadow: $shadow-raised;
  display: grid;
  place-items: center;
  align-content: center;
  row-gap: $sp-1;
  backface-visibility: hidden;
}

.face__tag {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  font-size: clamp(9px, 2.2vw, 11.5px);
  font-weight: 700;
  letter-spacing: .1em;
  color: $subject-ink;   // 크림 면 위 — 파랑은 4.25:1 미달이라 잉크로
}

.face__date {
  font-size: clamp(19px, 5.2vw, 31px);
  font-weight: 800;
  color: $subject-ink;
  white-space: nowrap;
}

.langs {
  display: flex;
  column-gap: $sp-2;
  margin: 0;
}

.langs__item {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  font-size: clamp(10px, 2.4vw, 13px);
  font-weight: 700;
  color: rgba($subject-cream, .72);   // .34 는 먹 무대 위 2.99:1 이었다 — AA 4.5
  border-radius: $r-pill;
  padding: 0 $sp-2;
}

// 같은 날짜가 세 서식으로 뒤집힌다
.stage.is-demo .face--ko { animation: flap $duration $easing infinite; }
.stage.is-demo .face--en { animation: flap $duration $easing infinite; animation-delay: calc($duration / -3); }
.stage.is-demo .face--ja { animation: flap $duration $easing infinite; animation-delay: calc($duration / -3 * 2); }
.stage.is-demo .langs__item { animation: lang-on $duration linear infinite; animation-delay: calc(var(--i) * #{$duration / 3}); }

@keyframes flap {
  0%       { transform: rotateX(-92deg); opacity: 0; }
  6%       { opacity: 1; }
  12%      { transform: rotateX(0deg); }
  27%      { transform: rotateX(0deg); opacity: 1; }
  34%      { transform: rotateX(92deg); opacity: 0; }
  100%     { transform: rotateX(92deg); opacity: 0; }
}
@keyframes lang-on {
  0%, 4%   { color: rgba($subject-cream, .72); transform: scale(1); }
  10%      { color: $subject-cream; transform: scale(1.12); }
  16%      { color: $subject-cream; transform: scale(1); }
  30%      { color: $subject-cream; }
  36%, 100%{ color: rgba($subject-cream, .72); transform: scale(1); }
}

@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .face--ko,
  .stage.is-demo .face--en,
  .stage.is-demo .face--ja,
  .stage.is-demo .langs__item { animation: none; }
  .face--en, .face--ja { opacity: 0; }
  .face--ko { transform: rotateX(0deg); }
}

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);
}

.flipwrap {
  display: grid;
  justify-items: center;
  row-gap: 12px;
  perspective: 640px;
}

.flip {
  position: relative;
  width: min(250px, 84vw);
  height: clamp(84px, 30vw, 118px);
  transform-style: preserve-3d;
}

.face {
  position: absolute;
  inset: 0;
  border-radius: 16px;
  background: #fff7e6;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  display: grid;
  place-items: center;
  align-content: center;
  row-gap: 4px;
  backface-visibility: hidden;
}

.face__tag {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  font-size: clamp(9px, 2.2vw, 11.5px);
  font-weight: 700;
  letter-spacing: 0.1em;
  color: #17141a;
}

.face__date {
  font-size: clamp(19px, 5.2vw, 31px);
  font-weight: 800;
  color: #17141a;
  white-space: nowrap;
}

.langs {
  display: flex;
  column-gap: 8px;
  margin: 0;
}

.langs__item {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  font-size: clamp(10px, 2.4vw, 13px);
  font-weight: 700;
  color: rgba(255, 247, 230, 0.72);
  border-radius: 999px;
  padding: 0 8px;
}

.stage.is-demo .face--ko {
  animation: flap 2s ease-out infinite;
}

.stage.is-demo .face--en {
  animation: flap 2s ease-out infinite;
  animation-delay: -0.6666666667s;
}

.stage.is-demo .face--ja {
  animation: flap 2s ease-out infinite;
  animation-delay: -1.3333333333s;
}

.stage.is-demo .langs__item {
  animation: lang-on 2s linear infinite;
  animation-delay: calc(var(--i) * 0.6666666667s);
}

@keyframes flap {
  0% {
    transform: rotateX(-92deg);
    opacity: 0;
  }
  6% {
    opacity: 1;
  }
  12% {
    transform: rotateX(0deg);
  }
  27% {
    transform: rotateX(0deg);
    opacity: 1;
  }
  34% {
    transform: rotateX(92deg);
    opacity: 0;
  }
  100% {
    transform: rotateX(92deg);
    opacity: 0;
  }
}
@keyframes lang-on {
  0%, 4% {
    color: rgba(255, 247, 230, 0.72);
    transform: scale(1);
  }
  10% {
    color: #fff7e6;
    transform: scale(1.12);
  }
  16% {
    color: #fff7e6;
    transform: scale(1);
  }
  30% {
    color: #fff7e6;
  }
  36%, 100% {
    color: rgba(255, 247, 230, 0.72);
    transform: scale(1);
  }
}
@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .face--ko,
  .stage.is-demo .face--en,
  .stage.is-demo .face--ja,
  .stage.is-demo .langs__item {
    animation: none;
  }
  .face--en, .face--ja {
    opacity: 0;
  }
  .face--ko {
    transform: rotateX(0deg);
  }
}

import type { CSSProperties } from "react";
import styles from "./DateFormatFlip.module.scss";

export type DateFormatFlipProps = {
  duration?: number;
  easing?: string;
  color?: string;
  formats?: { lang: string; date: string }[];
};

const DEFAULT_FORMATS = [
  { lang: "ko", date: "2026. 9. 11." },
  { lang: "en", date: "Sep 11, 2026" },
  { lang: "ja", date: "2026/09/11" },
];

export default function DateFormatFlip({
  duration = 2000,
  easing = "ease-out",
  color = "#fff7e6",
  formats = DEFAULT_FORMATS,
}: DateFormatFlipProps) {
  const vars: CSSProperties = { "--duration": `${duration}ms`, "--easing": easing, "--color": color } as CSSProperties;
  const faceClass = [styles.faceKo, styles.faceEn, styles.faceJa];
  return (
    <div className={styles.stage} style={vars} aria-label="날짜 형식 플립 데모" role="img">
      <div className={styles.flipwrap}>
        <div className={styles.flip}>
          {formats.slice(0, 3).map((f, i) => (
            <div key={f.lang} className={`${styles.face} ${faceClass[i]}`}>
              <span className={styles.tag}>{f.lang}</span>
              <span className={styles.date}>{f.date}</span>
            </div>
          ))}
        </div>
        <p className={styles.langs}>
          {formats.slice(0, 3).map((f, i) => (
            <span key={f.lang} className={styles.langsItem} style={{ "--i": i } as CSSProperties}>{f.lang}</span>
          ))}
        </p>
      </div>
    </div>
  );
}