06Empty state with add-morph

<main class="stage">
  <div class="es is-demo">
    <div class="es__stack">
      <div class="es__empty">
        <div class="es__box">
          <span class="es__shape es__shape--a" aria-hidden="true"></span>
          <span class="es__shape es__shape--b" aria-hidden="true"></span>
          <span class="es__shape es__shape--c" aria-hidden="true"></span>
        </div>
        <p class="es__title">No items yet</p>
        <p class="es__desc">Add your first item and it will appear here as a card.</p>
      </div>
      <div class="es__item" aria-hidden="true">
        <span class="es__item-dot" aria-hidden="true"></span>
        <div class="es__item-body">
          <strong>New project</strong>
          <span>Just added</span>
        </div>
      </div>
    </div>
    <button class="es__add" type="button">+ Add first item</button>
  </div>
</main>

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

$duration: $dur-enter;
$easing: $ease-spring;
$color: $subject-blue;

@include stage($stage-ink);

.es {
  box-sizing: border-box;
  width: min(280px, 84vw);
  text-align: center;
}
.es__stack { position: relative; min-height: 128px; }
.es__empty, .es__item {
  position: absolute; inset: 0;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  transition: opacity $duration $easing, transform $duration $easing;
}
.es__item { flex-direction: row; text-align: left; gap: $sp-3; padding: $sp-3; border-radius: $r-card;
  background: rgba(255, 247, 230, .06); border: 1px solid rgba(255, 247, 230, .14);
  opacity: 0; transform: scale(.9); pointer-events: none;
}
.es.is-added .es__item { opacity: 1; transform: scale(1); pointer-events: auto; }
.es.is-added .es__empty { opacity: 0; transform: scale(.9); pointer-events: none; }

.es__box { position: relative; width: 72px; height: 56px; margin: 0 auto $sp-3; }
.es__shape { position: absolute; border-radius: $r-sm; background: rgba(255, 247, 230, .14); border: 1px solid rgba(255, 247, 230, .24); }
.es__shape--a { width: 56px; height: 40px; left: 8px; top: 12px; animation: es-float 2s ease-in-out infinite; }
.es__shape--b { width: 22px; height: 22px; right: 0; top: 0; border-radius: 50%; background: $color; border-color: transparent; animation: es-float 2s ease-in-out infinite .15s; }
.es__shape--c { width: 30px; height: 8px; left: 18px; bottom: -2px; border-radius: $r-xs; animation: es-float 2s ease-in-out infinite .3s; }
@keyframes es-float {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-4px); }
}

.es__title { margin: 0 0 $sp-1; font-weight: 800; font-size: 13px; color: $subject-cream; }
.es__desc { margin: 0; font-size: 11px; line-height: 1.4; color: rgba(255, 247, 230, .58); }

.es__item-dot { flex: 0 0 auto; width: $sp-4; height: $sp-4; border-radius: 50%; background: $color; margin-top: $sp-1; }
.es__item-body { display: flex; flex-direction: column; gap: $sp-1; }
.es__item-body strong { font-size: 12px; color: $subject-cream; }
.es__item-body span { font-size: 10px; color: rgba(255, 247, 230, .55); }

.es__add {
  margin-top: $sp-4;
  border: 1px solid rgba(255, 247, 230, .3);
  background: transparent;
  color: $subject-cream;
  padding: $sp-2 $sp-4;
  border-radius: $r-control;
  font: inherit; font-weight: 700; font-size: 12px;
  cursor: pointer;
}

// ── 자동 루프: 빈 상태 ↔ 추가된 카드가 2초마다 서로 바뀐다 ──────────────
.es.is-demo .es__empty { animation: es-swap-out 2s $easing infinite; }
.es.is-demo .es__item { animation: es-swap-in 2s $easing infinite; }
@keyframes es-swap-out {
  0%, 45%  { opacity: 1; transform: scale(1); }
  60%, 100% { opacity: 0; transform: scale(.9); }
}
@keyframes es-swap-in {
  0%, 45%  { opacity: 0; transform: scale(.9); pointer-events: none; }
  60%, 100% { opacity: 1; transform: scale(1); pointer-events: none; }
}

@media (max-width: 340px) {
  .es__stack { min-height: 108px; }
  .es__box { width: 60px; height: 48px; }
}

@media (prefers-reduced-motion: reduce) {
  .es__shape { animation: none !important; }
  .es.is-demo .es__empty, .es.is-demo .es__item { animation: none !important; }
  .es__empty, .es__item { transition: 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);
}

.es {
  box-sizing: border-box;
  width: min(280px, 84vw);
  text-align: center;
}

.es__stack {
  position: relative;
  min-height: 128px;
}

.es__empty, .es__item {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  transition: opacity 600ms cubic-bezier(0.2, 0.8, 0.2, 1), transform 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.es__item {
  flex-direction: row;
  text-align: left;
  gap: 12px;
  padding: 12px;
  border-radius: 16px;
  background: rgba(255, 247, 230, 0.06);
  border: 1px solid rgba(255, 247, 230, 0.14);
  opacity: 0;
  transform: scale(0.9);
  pointer-events: none;
}

.es.is-added .es__item {
  opacity: 1;
  transform: scale(1);
  pointer-events: auto;
}

.es.is-added .es__empty {
  opacity: 0;
  transform: scale(0.9);
  pointer-events: none;
}

.es__box {
  position: relative;
  width: 72px;
  height: 56px;
  margin: 0 auto 12px;
}

.es__shape {
  position: absolute;
  border-radius: 8px;
  background: rgba(255, 247, 230, 0.14);
  border: 1px solid rgba(255, 247, 230, 0.24);
}

.es__shape--a {
  width: 56px;
  height: 40px;
  left: 8px;
  top: 12px;
  animation: es-float 2s ease-in-out infinite;
}

.es__shape--b {
  width: 22px;
  height: 22px;
  right: 0;
  top: 0;
  border-radius: 50%;
  background: #2f6df6;
  border-color: transparent;
  animation: es-float 2s ease-in-out infinite 0.15s;
}

.es__shape--c {
  width: 30px;
  height: 8px;
  left: 18px;
  bottom: -2px;
  border-radius: 4px;
  animation: es-float 2s ease-in-out infinite 0.3s;
}

@keyframes es-float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-4px);
  }
}
.es__title {
  margin: 0 0 4px;
  font-weight: 800;
  font-size: 13px;
  color: #fff7e6;
}

.es__desc {
  margin: 0;
  font-size: 11px;
  line-height: 1.4;
  color: rgba(255, 247, 230, 0.58);
}

.es__item-dot {
  flex: 0 0 auto;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: #2f6df6;
  margin-top: 4px;
}

.es__item-body {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.es__item-body strong {
  font-size: 12px;
  color: #fff7e6;
}

.es__item-body span {
  font-size: 10px;
  color: rgba(255, 247, 230, 0.55);
}

.es__add {
  margin-top: 16px;
  border: 1px solid rgba(255, 247, 230, 0.3);
  background: transparent;
  color: #fff7e6;
  padding: 8px 16px;
  border-radius: 12px;
  font: inherit;
  font-weight: 700;
  font-size: 12px;
  cursor: pointer;
}

.es.is-demo .es__empty {
  animation: es-swap-out 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.es.is-demo .es__item {
  animation: es-swap-in 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes es-swap-out {
  0%, 45% {
    opacity: 1;
    transform: scale(1);
  }
  60%, 100% {
    opacity: 0;
    transform: scale(0.9);
  }
}
@keyframes es-swap-in {
  0%, 45% {
    opacity: 0;
    transform: scale(0.9);
    pointer-events: none;
  }
  60%, 100% {
    opacity: 1;
    transform: scale(1);
    pointer-events: none;
  }
}
@media (max-width: 340px) {
  .es__stack {
    min-height: 108px;
  }
  .es__box {
    width: 60px;
    height: 48px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .es__shape {
    animation: none !important;
  }
  .es.is-demo .es__empty, .es.is-demo .es__item {
    animation: none !important;
  }
  .es__empty, .es__item {
    transition: none;
  }
}

// 실제 동작: 버튼을 누르면 빈 Status 일러스트가 실제로 카드 한 장으로 바뀐다(되돌리기도 가능).
var wrap = document.querySelector('.es');
var addBtn = document.querySelector('.es__add');
var item = document.querySelector('.es__item');
addBtn.addEventListener('click', function () {
  wrap.classList.remove('is-demo');
  var added = wrap.classList.toggle('is-added');
  item.setAttribute('aria-hidden', String(!added));
  addBtn.textContent = added ? 'Undo item' : '+ Add first item';
});

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

export type EmptyStateProps = {
  duration?: number;
  easing?: string;
  color?: string;
};

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

export default function EmptyState({ duration = 600, easing = "cubic-bezier(.2,.8,.2,1)", color = "#2f6df6" }: EmptyStateProps) {
  const [added, setAdded] = useState(false);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <div className={styles.es} style={vars}>
      <div className={styles.stack}>
        <div className={`${styles.empty} ${added ? styles.hide : ""}`}>
          <div className={styles.box}>
            <span className={`${styles.shape} ${styles.shapeA}`} />
            <span className={`${styles.shape} ${styles.shapeB}`} />
            <span className={`${styles.shape} ${styles.shapeC}`} />
          </div>
          <p className={styles.title}>아직 항목이 없어요</p>
          <p className={styles.desc}>첫 항목을 추가하면 여기에 카드로 나타납니다.</p>
        </div>
        <div className={`${styles.item} ${added ? styles.show : ""}`} aria-hidden={!added}>
          <span className={styles.itemDot} />
          <div className={styles.itemBody}>
            <strong>새 프로젝트</strong>
            <span>방금 추가됨</span>
          </div>
        </div>
      </div>
      <button type="button" className={styles.add} onClick={() => setAdded((v) => !v)}>
        {added ? "항목 되돌리기" : "+ 첫 항목 추가"}
      </button>
    </div>
  );
}