03Lắc lư như jello

<main class="stage">
  <div class="je is-demo">
    <button class="je__btn" type="button">Lưu</button>
    <p class="je__msg">Không lưu được. Vui lòng thử lại</p>
  </div>
</main>

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

$duration: 800ms;                                 // 출렁임이 잦아드는 데 걸리는 시간
$easing: $ease-out;
$color: $error;

@include stage($stage-orange);

.je { width: min(240px, 86vw); display: flex; flex-direction: column; align-items: center; gap: $sp-3; }
.je__btn {
  box-sizing: border-box;
  padding: $sp-2 $sp-6;
  border: 0;
  border-radius: $r-control;
  background: $subject-ink;
  color: $subject-cream;
  font-weight: 600;
  font-size: 14px;
  line-height: 1;
  font-family: inherit;
  transform-origin: center;
}
.je__msg { margin: 0; color: $subject-ink; font-weight: 500; font-size: 11px; line-height: 1.3; font-family: inherit; text-align: center; }

@keyframes je-jello {
  0%, 100% { transform: none; }
  15% { transform: skewX(-9deg) skewY(-9deg); }
  30% { transform: skewX(7deg) skewY(7deg); }
  45% { transform: skewX(-5deg) skewY(-5deg); }
  60% { transform: skewX(3deg) skewY(3deg); }
  75% { transform: skewX(-2deg) skewY(-2deg); }
  90% { transform: skewX(1deg) skewY(1deg); }
}
// 실제 동작: 저장 실패 응답을 받으면 .je--jello 가 한 번 붙는다
.je__btn.je--jello { animation: je-jello $duration $easing; }

// 데모 루프
.je.is-demo .je__btn { animation: je-jello $duration $easing infinite; }

@media (prefers-reduced-motion: reduce) {
  .je__btn.je--jello,
  .je.is-demo .je__btn { animation: none !important; }
}

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);
}

.je {
  width: min(240px, 86vw);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.je__btn {
  box-sizing: border-box;
  padding: 8px 24px;
  border: 0;
  border-radius: 12px;
  background: #17141a;
  color: #fff7e6;
  font-weight: 600;
  font-size: 14px;
  line-height: 1;
  font-family: inherit;
  transform-origin: center;
}

.je__msg {
  margin: 0;
  color: #17141a;
  font-weight: 500;
  font-size: 11px;
  line-height: 1.3;
  font-family: inherit;
  text-align: center;
}

@keyframes je-jello {
  0%, 100% {
    transform: none;
  }
  15% {
    transform: skewX(-9deg) skewY(-9deg);
  }
  30% {
    transform: skewX(7deg) skewY(7deg);
  }
  45% {
    transform: skewX(-5deg) skewY(-5deg);
  }
  60% {
    transform: skewX(3deg) skewY(3deg);
  }
  75% {
    transform: skewX(-2deg) skewY(-2deg);
  }
  90% {
    transform: skewX(1deg) skewY(1deg);
  }
}
.je__btn.je--jello {
  animation: je-jello 800ms ease-out;
}

.je.is-demo .je__btn {
  animation: je-jello 800ms ease-out infinite;
}

@media (prefers-reduced-motion: reduce) {
  .je__btn.je--jello,
  .je.is-demo .je__btn {
    animation: none !important;
  }
}

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

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

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

export default function JelloWobble({ duration = 800, easing = "ease-out", color = "#c2361a" }: JelloWobbleProps) {
  const [run, setRun] = useState(0);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <div className={styles.je} style={vars}>
      <button key={run} type="button" className={`${styles.btn} ${styles.jello}`} onClick={() => setRun((n) => n + 1)}>
        저장
      </button>
      <p className={styles.msg}>저장하지 못했습니다. 다시 시도하세요</p>
    </div>
  );
}