09Scroll zoom-out

<main class="stage is-demo">
  <div class="zoomout">
    <div class="zoomout__media" aria-hidden="true"></div>
    <span class="zoomout__label">Shrinks as you scroll</span>
  </div>
</main>

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

// ── 변수 3개. 변형은 이것만 바꾼다 ──────────────────────────
$scale-from: 1.45;                               // 처음 확대 배율
$duration: $dur-loop;                            // 데모 왕복 주기
$color: $subject-cream;                          // 라벨 글자 색 (ink 무대라 cream)

@include stage($stage-ink);

.zoomout {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
  display: grid;
  place-items: center;
}
.zoomout__media {
  position: absolute;
  inset: 6%;
  border-radius: $r-card;
  background: linear-gradient(135deg, rgba($color, .5), rgba($subject-blue, .5));
  transform: scale(#{$scale-from});

  // ── 실제 사용 코드: 확대돼 있던 화면이 스크롤할수록 줄어든다 ──
  @supports (animation-timeline: scroll()) {
    animation: zoom-out linear both;
    animation-timeline: scroll(root);
  }
}
.zoomout__label {
  position: relative;
  z-index: 1;
  padding: 10px 18px;
  border-radius: $r-pill;
  background: $stage-ink;
  border: 1px solid rgba($color, .5);
  color: $color;
  font: 700 clamp(12px, 3.8vw, 14px)/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

@keyframes zoom-out { from { transform: scale(#{$scale-from}); } to { transform: scale(1); } }

// ── 데모(.is-demo): 왕복 루프로 흉내 ────────
.stage.is-demo .zoomout__media { animation: zoom-loop $duration ease-in-out infinite; }
@keyframes zoom-loop { 0%, 100% { transform: scale(#{$scale-from}); } 50% { transform: scale(1); } }

@media (prefers-reduced-motion: reduce) {
  .zoomout__media, .stage.is-demo .zoomout__media { animation: none !important; transform: scale(1); }
}

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);
}

.zoomout {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
  display: grid;
  place-items: center;
}

.zoomout__media {
  position: absolute;
  inset: 6%;
  border-radius: 16px;
  background: linear-gradient(135deg, rgba(255, 247, 230, 0.5), rgba(47, 109, 246, 0.5));
  transform: scale(1.45);
}
@supports (animation-timeline: scroll()) {
  .zoomout__media {
    animation: zoom-out linear both;
    animation-timeline: scroll(root);
  }
}

.zoomout__label {
  position: relative;
  z-index: 1;
  padding: 10px 18px;
  border-radius: 999px;
  background: #17141a;
  border: 1px solid rgba(255, 247, 230, 0.5);
  color: #fff7e6;
  font: 700 clamp(12px, 3.8vw, 14px)/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

@keyframes zoom-out {
  from {
    transform: scale(1.45);
  }
  to {
    transform: scale(1);
  }
}
.stage.is-demo .zoomout__media {
  animation: zoom-loop 2s ease-in-out infinite;
}

@keyframes zoom-loop {
  0%, 100% {
    transform: scale(1.45);
  }
  50% {
    transform: scale(1);
  }
}
@media (prefers-reduced-motion: reduce) {
  .zoomout__media, .stage.is-demo .zoomout__media {
    animation: none !important;
    transform: scale(1);
  }
}

import type { CSSProperties, ReactNode } from "react";
import styles from "./ZoomOutScroll.module.scss";

export type ZoomOutScrollProps = {
  children: ReactNode;
  /** 처음 확대 배율 (기본 1.45) */
  scaleFrom?: number;
  /** 라벨 글자 색 */
  color?: string;
  className?: string;
};

type Vars = CSSProperties & { "--scale-from"?: string; "--color"?: string };

export default function ZoomOutScroll({
  children,
  scaleFrom = 1.45,
  color = "#fff7e6",
  className = "",
}: ZoomOutScrollProps) {
  const vars: Vars = { "--scale-from": `${scaleFrom}`, "--color": color };

  return (
    <div className={`${styles.wrap} ${className}`} style={vars}>
      <div className={styles.media} aria-hidden="true" />
      <span className={styles.label}>{children}</span>
    </div>
  );
}