06Fly-to-cart add

<main class="stage">
  <section class="cart is-demo" aria-label="Pressing Add flies a product dot on an arc to the cart">
    <input class="cart__check" type="checkbox" id="cart-add">
    <div class="cart__bag" aria-hidden="true">
      <span class="cart__basket"></span>
      <span class="cart__badge">2</span>
    </div>
    <article class="cart__product">
      <span class="cart__swatch" aria-hidden="true"></span>
      <h2 class="cart__name">Cozy mug 350ml</h2>
      <label class="cart__btn" for="cart-add">Add</label>
    </article>
    <span class="cart__fly" aria-hidden="true"><span class="cart__fly-y"></span></span>
  </section>
</main>

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

$duration: 700ms;                                 // 점이 카트까지 날아가는 시간
$easing: $ease-out;
$color: $stage-orange;                            // 상품·점 색

@include stage($stage-yellow);

.cart { position: relative; width: min(300px, 90vw); }
.cart__check { position: absolute; opacity: 0; pointer-events: none; }

// ── 오른쪽 위 장바구니 표시 + 개수 배지
.cart__bag { position: absolute; top: 0; right: 0; }
.cart__basket {
  position: relative;                 // 손잡이 ::before 가 바구니에 붙게
  display: block;
  width: 44px; height: 36px;
  box-sizing: border-box;
  border: 3px solid $stage-ink;
  border-radius: $r-xs $r-xs $r-sm $r-sm;          // 바구니 몸통
}
.cart__basket::before {                            // 손잡이
  content: "";
  position: absolute; top: -8px; left: 8px;
  width: 20px; height: 12px;
  border: 3px solid $stage-ink;
  border-bottom: 0;
  border-radius: $r-pill $r-pill 0 0;
}
.cart__badge {
  position: absolute; top: -8px; right: -8px;
  display: grid; place-items: center;
  min-width: 20px; height: 20px;
  padding: 0 4px;
  box-sizing: border-box;
  border-radius: $r-pill;
  background: $stage-ink;
  font-weight: 800;
  font-size: 11px;
  font-family: inherit;
  color: $stage-paper;
  transition: transform $dur-quick $ease-pop;
}
#cart-add:checked ~ .cart__bag .cart__badge { transform: scale(1.35); }

// ── 상품 카드
.cart__product {
  display: grid;
  gap: $sp-2;
  justify-items: start;
  margin-top: $sp-12;
  padding: $sp-4;
  width: 180px;
  box-sizing: border-box;
  border-radius: $r-card;
  background: $stage-paper;
  box-shadow: $shadow-press;
}
.cart__swatch {
  width: 56px; height: 56px;
  border-radius: 50%;
  background: $color;
}
.cart__name {
  margin: 0;
  font-weight: 800;
  font-size: clamp(13px, 3.8vw, 15px);
  font-family: inherit;
  color: $stage-ink;
}
.cart__btn {
  padding: $sp-1 $sp-4;
  border-radius: $r-control;
  background: $stage-ink;
  font-weight: 700;
  font-size: 13px;
  font-family: inherit;
  color: $stage-paper;
  cursor: pointer;
  transition: transform $dur-quick $easing;
}
.cart__btn:active { transform: scale(.94); }

// ── 날아가는 점: 겹 요소 2개로 포물선 (x 는 등속, y 는 느렸다 빨라짐)
.cart__fly {
  position: absolute; left: 16px; top: 64px;      // 상품 스와치 위치
  opacity: 0;
  transition: opacity $dur-quick linear;
  pointer-events: none;
  z-index: 2;
}
.cart__fly-y {
  display: block;
  width: 18px; height: 18px;
  border-radius: 50%;
  background: $color;
  box-shadow: $shadow-press;
}
#cart-add:checked ~ .cart__fly { transform: translateX(273px); opacity: 0; transition: transform $duration $easing, opacity $dur-quick linear $duration; }
#cart-add:checked ~ .cart__fly .cart__fly-y { transform: translateY(-71px); transition: transform $duration $easing; }

// 렌더·갤러리용 자동 루프: 대기 → 비행 → 배지 바운스 → 리셋
.cart.is-demo .cart__fly    { animation: fly-x $dur-loop linear infinite; opacity: 1; }
.cart.is-demo .cart__fly-y  { animation: fly-y $dur-loop $easing infinite; }
.cart.is-demo .cart__badge  { animation: badge-loop $dur-loop $easing infinite; }

@keyframes fly-x {
  0%, 30%    { transform: translateX(0);    opacity: 1; }
  68%, 100%  { transform: translateX(273px); opacity: 0; }
}
@keyframes fly-y {
  0%, 30%    { transform: translateY(0); }
  68%, 100%  { transform: translateY(-71px); }
}
@keyframes badge-loop {
  0%, 66%    { transform: scale(1); }
  74%        { transform: scale(1.35); }
  84%, 100%  { transform: scale(1); }
}

@media (max-width: 360px) {          // 320×200 아이프레임 대응 — 카드를 위로 붙인다
  .cart__product { margin-top: 8px; padding: 8px; width: 148px; gap: 4px; }
  .cart__swatch { width: 36px; height: 36px; }
  .cart__name { font-size: 12px; }
  .cart__btn { padding: 4px 12px; font-size: 11px; }
  .cart__fly { top: 40px; left: 12px; }
}

@media (prefers-reduced-motion: reduce) {
  .cart__badge, .cart__btn { transition: none; }
  .cart.is-demo .cart__fly,
  .cart.is-demo .cart__fly-y,
  .cart.is-demo .cart__badge { animation: none; }  // 점이 순간 이동, 배지는 고정
  .cart.is-demo .cart__fly { opacity: 0; }
  #cart-add:checked ~ .cart__fly { transform: translateX(273px); }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffd23f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.cart {
  position: relative;
  width: min(300px, 90vw);
}

.cart__check {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.cart__bag {
  position: absolute;
  top: 0;
  right: 0;
}

.cart__basket {
  position: relative;
  display: block;
  width: 44px;
  height: 36px;
  box-sizing: border-box;
  border: 3px solid #17141a;
  border-radius: 4px 4px 8px 8px;
}

.cart__basket::before {
  content: "";
  position: absolute;
  top: -8px;
  left: 8px;
  width: 20px;
  height: 12px;
  border: 3px solid #17141a;
  border-bottom: 0;
  border-radius: 999px 999px 0 0;
}

.cart__badge {
  position: absolute;
  top: -8px;
  right: -8px;
  display: grid;
  place-items: center;
  min-width: 20px;
  height: 20px;
  padding: 0 4px;
  box-sizing: border-box;
  border-radius: 999px;
  background: #17141a;
  font-weight: 800;
  font-size: 11px;
  font-family: inherit;
  color: #ffffff;
  transition: transform 220ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

#cart-add:checked ~ .cart__bag .cart__badge {
  transform: scale(1.35);
}

.cart__product {
  display: grid;
  gap: 8px;
  justify-items: start;
  margin-top: 48px;
  padding: 16px;
  width: 180px;
  box-sizing: border-box;
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
}

.cart__swatch {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: #ff4d1f;
}

.cart__name {
  margin: 0;
  font-weight: 800;
  font-size: clamp(13px, 3.8vw, 15px);
  font-family: inherit;
  color: #17141a;
}

.cart__btn {
  padding: 4px 16px;
  border-radius: 12px;
  background: #17141a;
  font-weight: 700;
  font-size: 13px;
  font-family: inherit;
  color: #ffffff;
  cursor: pointer;
  transition: transform 220ms ease-out;
}

.cart__btn:active {
  transform: scale(0.94);
}

.cart__fly {
  position: absolute;
  left: 16px;
  top: 64px;
  opacity: 0;
  transition: opacity 220ms linear;
  pointer-events: none;
  z-index: 2;
}

.cart__fly-y {
  display: block;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #ff4d1f;
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
}

#cart-add:checked ~ .cart__fly {
  transform: translateX(273px);
  opacity: 0;
  transition: transform 700ms ease-out, opacity 220ms linear 700ms;
}

#cart-add:checked ~ .cart__fly .cart__fly-y {
  transform: translateY(-71px);
  transition: transform 700ms ease-out;
}

.cart.is-demo .cart__fly {
  animation: fly-x 2s linear infinite;
  opacity: 1;
}

.cart.is-demo .cart__fly-y {
  animation: fly-y 2s ease-out infinite;
}

.cart.is-demo .cart__badge {
  animation: badge-loop 2s ease-out infinite;
}

@keyframes fly-x {
  0%, 30% {
    transform: translateX(0);
    opacity: 1;
  }
  68%, 100% {
    transform: translateX(273px);
    opacity: 0;
  }
}
@keyframes fly-y {
  0%, 30% {
    transform: translateY(0);
  }
  68%, 100% {
    transform: translateY(-71px);
  }
}
@keyframes badge-loop {
  0%, 66% {
    transform: scale(1);
  }
  74% {
    transform: scale(1.35);
  }
  84%, 100% {
    transform: scale(1);
  }
}
@media (max-width: 360px) {
  .cart__product {
    margin-top: 8px;
    padding: 8px;
    width: 148px;
    gap: 4px;
  }
  .cart__swatch {
    width: 36px;
    height: 36px;
  }
  .cart__name {
    font-size: 12px;
  }
  .cart__btn {
    padding: 4px 12px;
    font-size: 11px;
  }
  .cart__fly {
    top: 40px;
    left: 12px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .cart__badge, .cart__btn {
    transition: none;
  }
  .cart.is-demo .cart__fly,
  .cart.is-demo .cart__fly-y,
  .cart.is-demo .cart__badge {
    animation: none;
  }
  .cart.is-demo .cart__fly {
    opacity: 0;
  }
  #cart-add:checked ~ .cart__fly {
    transform: translateX(273px);
  }
}

import type { CSSProperties } from "react";
import { useEffect, useState } from "react";
import styles from "./FlyToCart.module.scss";

export type FlyToCartProps = {
  name: string;
  addLabel: string;
  /** 점이 카트까지 날아가는 시간 (기본 700ms) */
  duration?: number;
  easing?: string;
  /** 상품·점 색 */
  color?: string;
  /** 카트에 이미 담겨 있는 개수 */
  count?: number;
};

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

export default function FlyToCart({
  name,
  addLabel,
  duration = 700,
  easing = "ease-out",
  color = "#ff4d1f",
  count = 2,
}: FlyToCartProps) {
  const [flying, setFlying] = useState(false);
  const [added, setAdded] = useState(count);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  useEffect(() => {
    if (!flying) return;
    const t = setTimeout(() => { setAdded((n) => n + 1); setFlying(false); }, duration);
    return () => clearTimeout(t);
  }, [flying, duration]);

  return (
    <section className={styles.cart} style={vars} aria-label={name}>
      <div className={styles.bag} aria-hidden="true">
        <span className={styles.basket} />
        <span className={`${styles.badge} ${flying ? styles.badgeBump : ""}`}>{added}</span>
      </div>
      <article className={styles.product}>
        <span className={styles.swatch} aria-hidden="true" />
        <h2 className={styles.name}>{name}</h2>
        <button type="button" className={styles.btn} onClick={() => setFlying(true)}>{addLabel}</button>
      </article>
      <span className={`${styles.fly} ${flying ? styles.flyGo : ""}`} aria-hidden="true">
        <span className={styles.flyY} />
      </span>
    </section>
  );
}