07Anchor-positioned mini panel

<main class="stage">
  <article class="card is-demo" tabindex="0">
    <span class="card__media" aria-hidden="true"></span>
    <div class="card__body">
      <h3 class="card__title">Wireless Earbuds Pro</h3>
      <p class="card__meta">128,000 KRW</p>
    </div>
  </article>
  <div class="panel" aria-hidden="true">
    <p class="panel__row">12 in stock</p>
  </div>
</main>

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

$duration: $dur-base;                                    // 패널이 뜨는 시간
$easing: $ease-out;
$color: $subject-blue;                                     // 미디어 그라디언트

@include stage($stage-orange);
.stage { padding: clamp(8px, 2.4vw, 16px); }

.card {
  anchor-name: --c7;
  position: relative;
  width: min(150px, 48vw);
  aspect-ratio: 4 / 3;
  border-radius: $r-card;
  overflow: hidden;
  background: $stage-paper;
  box-shadow: $shadow-press;
  outline: none;
  cursor: pointer;
}
.card__media {
  position: absolute; inset: 0;
  background: linear-gradient(155deg, $color 0%, $stage-ink 100%);
}
.card__body {
  position: absolute; left: 0; right: 0; bottom: 0;
  padding: $sp-2 $sp-3;
  background: linear-gradient(0deg, rgba($stage-ink, .8), rgba($stage-ink, 0));
}
.card__title { margin: 0; font-weight: 700; font-size: clamp(11px, 3.2vw, 13px); line-height: 1.3; font-family: inherit; color: $stage-paper; }
.card__meta { margin: 0; font-weight: 500; font-size: clamp(10px, 2.8vw, 11px); line-height: 1.3; font-family: inherit; color: rgba($stage-paper, .85); }

// CSS 앵커 포지셔닝 — 카드가 어디 있든 anchor-name 만 맞으면 패널이 그 아래에 자동으로 붙는다
.panel {
  position: absolute;
  position-anchor: --c7;
  position-area: block-end;
  position-try-fallbacks: flip-block;
  margin-top: $sp-1;
  width: min(150px, 48vw);
  box-sizing: border-box;
  padding: $sp-1 $sp-2;
  border-radius: $r-sm;
  background: $stage-ink;
  color: $stage-paper;
  font-weight: 500; font-size: 11px; line-height: 1.4; font-family: inherit;
  white-space: nowrap;
  text-align: center;
  opacity: 0;
  transform: translateY(-6px);
  transition: opacity $duration $easing, transform $duration $easing;
  pointer-events: none;
  z-index: 5;
}
.panel__row { margin: 0; }

.card:hover ~ .panel,
.card:focus-visible ~ .panel {
  opacity: 1;
  transform: translateY(0);
}
.card.is-demo ~ .panel { animation: panel-loop $dur-loop $easing infinite; }
@keyframes panel-loop {
  0%, 20%  { opacity: 0; transform: translateY(-6px); }
  50%, 75% { opacity: 1; transform: translateY(0); }
  100%     { opacity: 0; transform: translateY(-6px); }
}

@media (prefers-reduced-motion: reduce) {
  .panel { transition: none; }
  .card.is-demo ~ .panel { animation: none; opacity: 1; transform: translateY(0); }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ff4d1f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.stage {
  padding: clamp(8px, 2.4vw, 16px);
}

.card {
  anchor-name: --c7;
  position: relative;
  width: min(150px, 48vw);
  aspect-ratio: 4/3;
  border-radius: 16px;
  overflow: hidden;
  background: #ffffff;
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
  outline: none;
  cursor: pointer;
}

.card__media {
  position: absolute;
  inset: 0;
  background: linear-gradient(155deg, #2f6df6 0%, #17141a 100%);
}

.card__body {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 8px 12px;
  background: linear-gradient(0deg, rgba(23, 20, 26, 0.8), rgba(23, 20, 26, 0));
}

.card__title {
  margin: 0;
  font-weight: 700;
  font-size: clamp(11px, 3.2vw, 13px);
  line-height: 1.3;
  font-family: inherit;
  color: #ffffff;
}

.card__meta {
  margin: 0;
  font-weight: 500;
  font-size: clamp(10px, 2.8vw, 11px);
  line-height: 1.3;
  font-family: inherit;
  color: rgba(255, 255, 255, 0.85);
}

.panel {
  position: absolute;
  position-anchor: --c7;
  position-area: block-end;
  position-try-fallbacks: flip-block;
  margin-top: 4px;
  width: min(150px, 48vw);
  box-sizing: border-box;
  padding: 4px 8px;
  border-radius: 8px;
  background: #17141a;
  color: #ffffff;
  font-weight: 500;
  font-size: 11px;
  line-height: 1.4;
  font-family: inherit;
  white-space: nowrap;
  text-align: center;
  opacity: 0;
  transform: translateY(-6px);
  transition: opacity 300ms ease-out, transform 300ms ease-out;
  pointer-events: none;
  z-index: 5;
}

.panel__row {
  margin: 0;
}

.card:hover ~ .panel,
.card:focus-visible ~ .panel {
  opacity: 1;
  transform: translateY(0);
}

.card.is-demo ~ .panel {
  animation: panel-loop 2s ease-out infinite;
}

@keyframes panel-loop {
  0%, 20% {
    opacity: 0;
    transform: translateY(-6px);
  }
  50%, 75% {
    opacity: 1;
    transform: translateY(0);
  }
  100% {
    opacity: 0;
    transform: translateY(-6px);
  }
}
@media (prefers-reduced-motion: reduce) {
  .panel {
    transition: none;
  }
  .card.is-demo ~ .panel {
    animation: none;
    opacity: 1;
    transform: translateY(0);
  }
}

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

export type AnchoredPanelCardProps = {
  title: string;
  meta: string;
  panel: string;
  /** 패널이 뜨는 시간 (기본 300ms) */
  duration?: number;
  easing?: string;
  /** 미디어 그라디언트 색 */
  color?: string;
};

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

/** CSS 앵커 포지셔닝 — anchor-name 만 맞으면 패널이 카드 아래에 자동으로 붙는다 (JS 없음) */
export default function AnchoredPanelCard({
  title,
  meta,
  panel,
  duration = 300,
  easing = "ease-out",
  color = "#2f6df6",
}: AnchoredPanelCardProps) {
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <div className={styles.wrap} style={vars}>
      <article className={styles.card} tabIndex={0}>
        <span className={styles.media} aria-hidden="true" />
        <div className={styles.body}>
          <h3 className={styles.title}>{title}</h3>
          <p className={styles.meta}>{meta}</p>
        </div>
      </article>
      <div className={styles.panel} aria-hidden="true">
        <p className={styles.panelRow}>{panel}</p>
      </div>
    </div>
  );
}