01Trồi lên xuất hiện

<main class="stage">
  <article class="card is-demo">
    <p class="card__eyebrow">SECTION</p>
    <h2 class="card__title">Trồi lên xuất hiện</h2>
    <p class="card__body">Khi cuộn tới, phần tử trồi nhẹ lên từ phía dưới rồi hiện ra.</p>
  </article>
</main>

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

// ── 변수 3개. 변형은 이것만 바꾼다 (값은 토큰에서 받는다) ──────
$distance: 24px;                                 // 올라오는 거리. 멀리 두려면 48px
$duration: $dur-enter;                           // 등장이 다 끝나는 데 걸리는 진행 구간
$easing: $ease-out;                              // 처음 빠르고 끝은 느리게

// ── 데모 무대 (zip 에서 지워도 된다) ──────────────────────────
@include stage($stage-ink);

// ── 카드 (피사체: ink 무대라 blue) ───────────────────────────
.card {
  box-sizing: border-box;
  width: min(300px, 100%);
  padding: clamp(16px, 6vw, 26px) clamp(16px, 6vw, 24px);
  border-radius: $r-card;
  background: $subject-blue-deep;
  color: #fff;
  text-align: left;

  &__eyebrow { margin: 0 0 6px; font-weight: 700; font-size: 11px; line-height: 1; font-family: inherit; letter-spacing: .12em; color: $subject-cream; }
  &__title { margin: 0 0 8px; font-weight: 700; font-size: clamp(16px, 5vw, 20px); line-height: 1.3; font-family: inherit; }
  &__body { margin: 0; font-weight: 400; font-size: 14px; line-height: 1.5; font-family: inherit; color: $subject-cream; }

  // ── 실제 사용 코드: 스크롤이 곧 애니메이션 시계다 (zip 그대로) ──
  // 요소가 뷰포트로 들어오는 구간(entry)만큼 진행된다. JS 0줄.
  @supports (animation-timeline: view()) {
    animation: fade-up-reveal $easing both;
    animation-timeline: view();
    animation-range: entry 0% cover 30%;
  }

  // ── 미지원 브라우저: 움직이지 않고 그냥 보여준다 (정직한 대체) ──
  @supports not (animation-timeline: view()) {
    opacity: 1;
    transform: none;
  }
}

@keyframes fade-up-reveal {
  from { opacity: 0; transform: translateY($distance); }
  to   { opacity: 1; transform: translateY(0); }
}

// ── 데모(.is-demo): 렌더러가 프레임을 뽑도록 스크롤 대신 2초 루프로 흉내 ──
.card.is-demo {
  animation: fade-up-loop $dur-loop $easing infinite;
}
@keyframes fade-up-loop {
  0%   { opacity: 0; transform: translateY($distance * 2); }
  30%  { opacity: 1; transform: translateY(0); }
  75%  { opacity: 1; transform: translateY(0); }
  100% { opacity: 0; transform: translateY($distance * 2); }
}

// ── 접근성: 움직임 줄이기 설정이면 즉시 보여주기만 ────────────
@media (prefers-reduced-motion: reduce) {
  .card, .card.is-demo { animation: none !important; opacity: 1; 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);
}

.card {
  box-sizing: border-box;
  width: min(300px, 100%);
  padding: clamp(16px, 6vw, 26px) clamp(16px, 6vw, 24px);
  border-radius: 16px;
  background: #0a4fe8;
  color: #fff;
  text-align: left;
}
.card__eyebrow {
  margin: 0 0 6px;
  font-weight: 700;
  font-size: 11px;
  line-height: 1;
  font-family: inherit;
  letter-spacing: 0.12em;
  color: #fff7e6;
}
.card__title {
  margin: 0 0 8px;
  font-weight: 700;
  font-size: clamp(16px, 5vw, 20px);
  line-height: 1.3;
  font-family: inherit;
}
.card__body {
  margin: 0;
  font-weight: 400;
  font-size: 14px;
  line-height: 1.5;
  font-family: inherit;
  color: #fff7e6;
}
@supports (animation-timeline: view()) {
  .card {
    animation: fade-up-reveal ease-out both;
    animation-timeline: view();
    animation-range: entry 0% cover 30%;
  }
}
@supports not (animation-timeline: view()) {
  .card {
    opacity: 1;
    transform: none;
  }
}

@keyframes fade-up-reveal {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
.card.is-demo {
  animation: fade-up-loop 2s ease-out infinite;
}

@keyframes fade-up-loop {
  0% {
    opacity: 0;
    transform: translateY(48px);
  }
  30% {
    opacity: 1;
    transform: translateY(0);
  }
  75% {
    opacity: 1;
    transform: translateY(0);
  }
  100% {
    opacity: 0;
    transform: translateY(48px);
  }
}
@media (prefers-reduced-motion: reduce) {
  .card, .card.is-demo {
    animation: none !important;
    opacity: 1;
    transform: none;
  }
}

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

export type FadeUpRevealProps = {
  eyebrow?: string;
  title: string;
  children: ReactNode;
  /** 올라오는 거리 (기본 24px) */
  distance?: number;
  /** 등장이 끝나는 구간 (기본 700ms) — animation-range 계산에는 안 쓰이고 문서용 */
  duration?: number;
  /** easing (기본 ease-out) */
  easing?: string;
  className?: string;
};

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

export default function FadeUpReveal({
  eyebrow = "SECTION",
  title,
  children,
  distance = 24,
  duration = 700,
  easing = "ease-out",
  className = "",
}: FadeUpRevealProps) {
  const vars: Vars = {
    "--distance": `${distance}px`,
    "--duration": `${duration}ms`,
    "--easing": easing,
  };

  return (
    <article className={`${styles.card} ${className}`} style={vars}>
      <p className={styles.eyebrow}>{eyebrow}</p>
      <h2 className={styles.title}>{title}</h2>
      <p className={styles.body}>{children}</p>
    </article>
  );
}