01ブラインド開閉の登場

<main class="stage">
  <section class="reveal is-demo" aria-label="ブラインドが折りたたまれ春の見出しが現れる">
    <div class="reveal__panel">
      <p class="reveal__kicker">春シーズン開幕</p>
      <h2 class="reveal__headline">新コレクション 20%オフ</h2>
    </div>
    <div class="reveal__slats" aria-hidden="true">
      <span class="reveal__slat"></span>
      <span class="reveal__slat"></span>
      <span class="reveal__slat"></span>
      <span class="reveal__slat"></span>
      <span class="reveal__slat"></span>
      <span class="reveal__slat"></span>
    </div>
  </section>
</main>

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

$duration: 1.2s;                                  // 브라인드 한 살이 접히는 시간
$easing: $ease-out;
$color: $subject-blue;                            // 패널 그라데이션 시작색

@include stage($stage-ink);

.reveal {
  position: relative;
  width: min(320px, 88vw);
  height: clamp(150px, 52vh, 180px);
  border-radius: $r-card;
  overflow: hidden;
}
.reveal__panel {
  position: absolute; inset: 0;
  display: grid;
  align-content: center;
  gap: $sp-2;
  padding: $sp-4;
  background: linear-gradient(135deg, $color 0%, $stage-yellow 100%);
}
.reveal__kicker {
  margin: 0;
  font-weight: 700;
  font-size: clamp(11px, 3vw, 13px);
  font-family: inherit;
  color: $stage-ink;
  letter-spacing: 2px;
}
.reveal__headline {
  margin: 0;
  font-weight: 800;
  font-size: clamp(18px, 5.4vw, 26px);
  line-height: 1.25;
  font-family: inherit;
  color: $stage-paper;
}
.reveal__slats {
  position: absolute; inset: 0;
  display: flex;
  flex-direction: column;
}
.reveal__slat {
  flex: 1;
  background: $stage-paper;
  border-bottom: 2px solid rgba(23, 20, 26, .12);
  transform-origin: top center; // 규칙8: 윗변서 접힘
  transform: scaleY(1);
}

// 실사용: 페이지 첫 등장에 한 번 — 살마다 90ms 늦게 위→아래로 접힌다
@keyframes slat-open { from { transform: scaleY(1); } to { transform: scaleY(0); } }
@for $i from 1 through 6 {
  .reveal__slat:nth-child(#{$i}) {
    animation: slat-open $duration $easing (($i - 1) * 90ms) both;
  }
}

// 렌더·갤러리용 자동 루프: 닫힘 → 열림 파동 → 다시 닫힘 (2초 주기 안에서 계단 재현)
@for $i from 1 through 6 {
  .reveal.is-demo .reveal__slat:nth-child(#{$i}) {
    animation: slat-loop-#{$i} $dur-loop $easing infinite;
  }
  @keyframes slat-loop-#{$i} {
    0%, 8%      { transform: scaleY(1); }
    #{10 + $i * 6}%, 78% { transform: scaleY(0); }
    92%, 100%   { transform: scaleY(1); }
  }
}

@media (prefers-reduced-motion: reduce) {
  .reveal__slat,
  .reveal.is-demo .reveal__slat {
    animation: none;
    transform: scaleY(0);            // 접힌 최종 상태 — 문구가 바로 보인다
  }
}

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);
}

.reveal {
  position: relative;
  width: min(320px, 88vw);
  height: clamp(150px, 52vh, 180px);
  border-radius: 16px;
  overflow: hidden;
}

.reveal__panel {
  position: absolute;
  inset: 0;
  display: grid;
  align-content: center;
  gap: 8px;
  padding: 16px;
  background: linear-gradient(135deg, #2f6df6 0%, #ffd23f 100%);
}

.reveal__kicker {
  margin: 0;
  font-weight: 700;
  font-size: clamp(11px, 3vw, 13px);
  font-family: inherit;
  color: #17141a;
  letter-spacing: 2px;
}

.reveal__headline {
  margin: 0;
  font-weight: 800;
  font-size: clamp(18px, 5.4vw, 26px);
  line-height: 1.25;
  font-family: inherit;
  color: #ffffff;
}

.reveal__slats {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
}

.reveal__slat {
  flex: 1;
  background: #ffffff;
  border-bottom: 2px solid rgba(23, 20, 26, 0.12);
  transform-origin: top center;
  transform: scaleY(1);
}

@keyframes slat-open {
  from {
    transform: scaleY(1);
  }
  to {
    transform: scaleY(0);
  }
}
.reveal__slat:nth-child(1) {
  animation: slat-open 1.2s ease-out 0ms both;
}

.reveal__slat:nth-child(2) {
  animation: slat-open 1.2s ease-out 90ms both;
}

.reveal__slat:nth-child(3) {
  animation: slat-open 1.2s ease-out 180ms both;
}

.reveal__slat:nth-child(4) {
  animation: slat-open 1.2s ease-out 270ms both;
}

.reveal__slat:nth-child(5) {
  animation: slat-open 1.2s ease-out 360ms both;
}

.reveal__slat:nth-child(6) {
  animation: slat-open 1.2s ease-out 450ms both;
}

.reveal.is-demo .reveal__slat:nth-child(1) {
  animation: slat-loop-1 2s ease-out infinite;
}

@keyframes slat-loop-1 {
  0%, 8% {
    transform: scaleY(1);
  }
  16%, 78% {
    transform: scaleY(0);
  }
  92%, 100% {
    transform: scaleY(1);
  }
}
.reveal.is-demo .reveal__slat:nth-child(2) {
  animation: slat-loop-2 2s ease-out infinite;
}

@keyframes slat-loop-2 {
  0%, 8% {
    transform: scaleY(1);
  }
  22%, 78% {
    transform: scaleY(0);
  }
  92%, 100% {
    transform: scaleY(1);
  }
}
.reveal.is-demo .reveal__slat:nth-child(3) {
  animation: slat-loop-3 2s ease-out infinite;
}

@keyframes slat-loop-3 {
  0%, 8% {
    transform: scaleY(1);
  }
  28%, 78% {
    transform: scaleY(0);
  }
  92%, 100% {
    transform: scaleY(1);
  }
}
.reveal.is-demo .reveal__slat:nth-child(4) {
  animation: slat-loop-4 2s ease-out infinite;
}

@keyframes slat-loop-4 {
  0%, 8% {
    transform: scaleY(1);
  }
  34%, 78% {
    transform: scaleY(0);
  }
  92%, 100% {
    transform: scaleY(1);
  }
}
.reveal.is-demo .reveal__slat:nth-child(5) {
  animation: slat-loop-5 2s ease-out infinite;
}

@keyframes slat-loop-5 {
  0%, 8% {
    transform: scaleY(1);
  }
  40%, 78% {
    transform: scaleY(0);
  }
  92%, 100% {
    transform: scaleY(1);
  }
}
.reveal.is-demo .reveal__slat:nth-child(6) {
  animation: slat-loop-6 2s ease-out infinite;
}

@keyframes slat-loop-6 {
  0%, 8% {
    transform: scaleY(1);
  }
  46%, 78% {
    transform: scaleY(0);
  }
  92%, 100% {
    transform: scaleY(1);
  }
}
@media (prefers-reduced-motion: reduce) {
  .reveal__slat,
  .reveal.is-demo .reveal__slat {
    animation: none;
    transform: scaleY(0);
  }
}

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

export type BlindsSlatRevealProps = {
  kicker: string;
  headline: string;
  /** 살이 전부 접히는 데 걸리는 시간 (기본 1200ms) */
  duration?: number;
  easing?: string;
  /** 패널 그라데이션 시작색 */
  color?: string;
  /** 블라인드 살 개수 (기본 6) */
  slats?: number;
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };

export default function BlindsSlatReveal({
  kicker,
  headline,
  duration = 1200,
  easing = "ease-out",
  color = "#2f6df6",
  slats = 6,
}: BlindsSlatRevealProps) {
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <section className={styles.reveal} style={vars} aria-label={headline}>
      <div className={styles.panel}>
        <p className={styles.kicker}>{kicker}</p>
        <h2 className={styles.headline}>{headline}</h2>
      </div>
      <div className={styles.slats} aria-hidden="true">
        {Array.from({ length: slats }, (_, i) => (
          <span key={i} className={styles.slat} style={{ animationDelay: `${i * 90}ms` }} />
        ))}
      </div>
    </section>
  );
}