01Float up and down

<main class="stage">
  <div class="badge a-float">
    <span class="badge__dot" aria-hidden="true"></span>
    New arrival
  </div>
</main>

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

// ── 변수 3개. 변형은 이것만 바꾼다 ──────────────────────
$duration: 3s;                 // 한 번 오가는 데 걸리는 시간
$easing: ease-in-out;          // 뜨고 가라앉는 리듬이라 스프링보다 사인 곡선에 가까운 이 값을 쓴다
$color: $subject-blue;         // 점 색

// ── 데모 무대 ───────────────────────────────
@include stage($stage-ink);

// ── 배지: .a-float 하나만 붙이면 어떤 요소든 떠오른다 ─────
.badge {
  display: inline-flex;
  align-items: center;
  gap: clamp(8px, 3vw, 12px);
  padding: clamp(14px, 4vw, 18px) clamp(24px, 6vw, 32px);
  border-radius: $r-pill;
  background: $subject-cream;
  color: $stage-ink;
  font-weight: 700; font-size: clamp(16px, 4.5vw, 20px); line-height: 1; font-family: inherit;
  box-shadow: $shadow-raised;
}
.badge__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: $color;
  flex: none;
}

.a-float {
  animation: float $duration $easing infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-16px); }
}

// ── 접근성: 움직임 줄이기 설정이면 뜨지 않는다 ──────────────
@media (prefers-reduced-motion: reduce) {
  .a-float { animation: 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);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: clamp(8px, 3vw, 12px);
  padding: clamp(14px, 4vw, 18px) clamp(24px, 6vw, 32px);
  border-radius: 999px;
  background: #fff7e6;
  color: #17141a;
  font-weight: 700;
  font-size: clamp(16px, 4.5vw, 20px);
  line-height: 1;
  font-family: inherit;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
}

.badge__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #2f6df6;
  flex: none;
}

.a-float {
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-16px);
  }
}
@media (prefers-reduced-motion: reduce) {
  .a-float {
    animation: none;
  }
}

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

export type FloatBadgeProps = {
  children: ReactNode;
  /** 한 번 오가는 데 걸리는 시간 (기본 3000ms) */
  duration?: number;
  /** CSS easing (기본 ease-in-out) */
  easing?: string;
  /** 점 색 */
  color?: string;
};

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

export default function FloatBadge({
  children,
  duration = 3000,
  easing = "ease-in-out",
  color = "#2f6df6",
}: FloatBadgeProps) {
  const vars: Vars = {
    "--duration": `${duration}ms`,
    "--easing": easing,
    "--color": color,
  };
  return (
    <div className={styles.badge} style={vars}>
      <span className={styles.dot} aria-hidden="true" />
      {children}
    </div>
  );
}