02Save-to-check animation

<main class="stage">
  <button class="save is-demo" type="button">
    <span class="save__icon" aria-hidden="true">
      <span class="save__ring"></span>
      <span class="save__disk"></span>
      <span class="save__check">
        <span class="save__check-bar save__check-bar--short"></span>
        <span class="save__check-bar save__check-bar--long"></span>
      </span>
    </span>
    <span class="save__label">Save</span>
  </button>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-base;                              // 디스켓 → 체크 전환 시간
$easing: $ease-pop;                                // 배지가 팝업하는 이징
$color: $subject-blue;                              // 완료 배지 강조색

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

.save {
  display: inline-flex;
  align-items: center;
  gap: clamp(8px, 2.6vw, 12px);
  border: 0;
  border-radius: $r-control;
  padding: clamp(12px, 4vw, 16px) clamp(18px, 5.6vw, 24px);
  font-weight: 700;
  font-size: clamp(14px, 4vw, 17px);
  line-height: 1;
  font-family: inherit;
  color: $stage-ink;
  background: $subject-cream;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;

  &__icon { position: relative; width: 24px; height: 24px; flex: none; }

  // 배지: 원형이 팝업하며 완료를 알린다
  &__ring {
    position: absolute; inset: -3px;
    border-radius: 50%;
    background: $color;
    opacity: 0;
    transform: scale(.4);
  }

  // 디스켓: 사각 + 오른쪽 위 노치
  &__disk {
    position: absolute; inset: 0;
    border: 2.4px solid currentColor;
    border-radius: 4px;
    opacity: 1;
    transform: scale(1);
    &::after {
      content: "";
      position: absolute; top: 3px; right: 3px;
      width: 7px; height: 6px;
      background: currentColor;
    }
  }

  // 체크: 두 개의 획이 각각 scaleX 로 그어진다
  &__check { position: absolute; inset: 0; color: $subject-cream; }
  &__check-bar {
    position: absolute;
    height: 3px;
    border-radius: 2px;
    background: currentColor;
    transform: scaleX(0);
    transform-origin: left center; // 규칙8: 체크 막대 같은 꼭짓점
  }
  &__check-bar--short { width: 6px; left: 8px; top: 14px; transform: rotate(225deg) scaleX(0); }   // 두 막대가 같은 꼭짓점(8,14)에서 출발 — 어긋남 0
  &__check-bar--long  { width: 13px; left: 8px; top: 14px; transform: rotate(-52deg) scaleX(0); }

  &.is-saved &__ring  { animation: ring-pop $duration $easing forwards; }
  &.is-saved &__disk  { animation: disk-out $duration $easing forwards; }
  &.is-saved &__check-bar--short { animation: check-short $duration $easing forwards; animation-delay: $duration * .35; }
  &.is-saved &__check-bar--long  { animation: check-long $duration $easing forwards; animation-delay: $duration * .5; }

  &.is-demo &__ring  { animation: ring-pop-loop $dur-loop $easing infinite; }
  &.is-demo &__disk  { animation: disk-out-loop $dur-loop $easing infinite; }
  &.is-demo &__check-bar--short { animation: check-short-loop $dur-loop $easing infinite; }
  &.is-demo &__check-bar--long  { animation: check-long-loop $dur-loop $easing infinite; }
}

@keyframes ring-pop  { from { opacity: 0; transform: scale(.4); } to { opacity: 1; transform: scale(1); } }
@keyframes disk-out  { from { opacity: 1; transform: scale(1); } to { opacity: 0; transform: scale(.5); } }
@keyframes check-short { to { transform: rotate(225deg) scaleX(1); } }
@keyframes check-long  { to { transform: rotate(-52deg) scaleX(1); } }

@keyframes ring-pop-loop {
  0%, 20%  { opacity: 0; transform: scale(.4); }
  40%, 85% { opacity: 1; transform: scale(1); }
  100%     { opacity: 0; transform: scale(.4); }
}
@keyframes disk-out-loop {
  0%, 20%  { opacity: 1; transform: scale(1); }
  40%, 85% { opacity: 0; transform: scale(.5); }
  100%     { opacity: 1; transform: scale(1); }
}
@keyframes check-short-loop {
  0%, 27%  { transform: rotate(225deg) scaleX(0); }
  45%, 85% { transform: rotate(225deg) scaleX(1); }
  100%     { transform: rotate(225deg) scaleX(0); }
}
@keyframes check-long-loop {
  0%, 32%  { transform: rotate(-52deg) scaleX(0); }
  50%, 85% { transform: rotate(-52deg) scaleX(1); }
  100%     { transform: rotate(-52deg) scaleX(0); }
}

// ── 접근성: 움직임 줄이기 설정이면 상태만 바뀌고 과정은 생략 ────
@media (prefers-reduced-motion: reduce) {
  .save__ring, .save__disk, .save__check-bar { animation: none !important; }
  .save.is-saved .save__ring { opacity: 1; transform: scale(1); }
  .save.is-saved .save__disk { opacity: 0; }
  .save.is-saved .save__check-bar--short { transform: rotate(225deg) scaleX(1); }
  .save.is-saved .save__check-bar--long  { transform: rotate(-52deg) scaleX(1); }
}

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);
}

.save {
  display: inline-flex;
  align-items: center;
  gap: clamp(8px, 2.6vw, 12px);
  border: 0;
  border-radius: 12px;
  padding: clamp(12px, 4vw, 16px) clamp(18px, 5.6vw, 24px);
  font-weight: 700;
  font-size: clamp(14px, 4vw, 17px);
  line-height: 1;
  font-family: inherit;
  color: #17141a;
  background: #fff7e6;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}
.save__icon {
  position: relative;
  width: 24px;
  height: 24px;
  flex: none;
}
.save__ring {
  position: absolute;
  inset: -3px;
  border-radius: 50%;
  background: #2f6df6;
  opacity: 0;
  transform: scale(0.4);
}
.save__disk {
  position: absolute;
  inset: 0;
  border: 2.4px solid currentColor;
  border-radius: 4px;
  opacity: 1;
  transform: scale(1);
}
.save__disk::after {
  content: "";
  position: absolute;
  top: 3px;
  right: 3px;
  width: 7px;
  height: 6px;
  background: currentColor;
}
.save__check {
  position: absolute;
  inset: 0;
  color: #fff7e6;
}
.save__check-bar {
  position: absolute;
  height: 3px;
  border-radius: 2px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left center;
}
.save__check-bar--short {
  width: 6px;
  left: 8px;
  top: 14px;
  transform: rotate(225deg) scaleX(0);
}
.save__check-bar--long {
  width: 13px;
  left: 8px;
  top: 14px;
  transform: rotate(-52deg) scaleX(0);
}
.save.is-saved .save__ring {
  animation: ring-pop 300ms cubic-bezier(0.2, 1.4, 0.4, 1) forwards;
}
.save.is-saved .save__disk {
  animation: disk-out 300ms cubic-bezier(0.2, 1.4, 0.4, 1) forwards;
}
.save.is-saved .save__check-bar--short {
  animation: check-short 300ms cubic-bezier(0.2, 1.4, 0.4, 1) forwards;
  animation-delay: 105ms;
}
.save.is-saved .save__check-bar--long {
  animation: check-long 300ms cubic-bezier(0.2, 1.4, 0.4, 1) forwards;
  animation-delay: 150ms;
}
.save.is-demo .save__ring {
  animation: ring-pop-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}
.save.is-demo .save__disk {
  animation: disk-out-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}
.save.is-demo .save__check-bar--short {
  animation: check-short-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}
.save.is-demo .save__check-bar--long {
  animation: check-long-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

@keyframes ring-pop {
  from {
    opacity: 0;
    transform: scale(0.4);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}
@keyframes disk-out {
  from {
    opacity: 1;
    transform: scale(1);
  }
  to {
    opacity: 0;
    transform: scale(0.5);
  }
}
@keyframes check-short {
  to {
    transform: rotate(225deg) scaleX(1);
  }
}
@keyframes check-long {
  to {
    transform: rotate(-52deg) scaleX(1);
  }
}
@keyframes ring-pop-loop {
  0%, 20% {
    opacity: 0;
    transform: scale(0.4);
  }
  40%, 85% {
    opacity: 1;
    transform: scale(1);
  }
  100% {
    opacity: 0;
    transform: scale(0.4);
  }
}
@keyframes disk-out-loop {
  0%, 20% {
    opacity: 1;
    transform: scale(1);
  }
  40%, 85% {
    opacity: 0;
    transform: scale(0.5);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}
@keyframes check-short-loop {
  0%, 27% {
    transform: rotate(225deg) scaleX(0);
  }
  45%, 85% {
    transform: rotate(225deg) scaleX(1);
  }
  100% {
    transform: rotate(225deg) scaleX(0);
  }
}
@keyframes check-long-loop {
  0%, 32% {
    transform: rotate(-52deg) scaleX(0);
  }
  50%, 85% {
    transform: rotate(-52deg) scaleX(1);
  }
  100% {
    transform: rotate(-52deg) scaleX(0);
  }
}
@media (prefers-reduced-motion: reduce) {
  .save__ring, .save__disk, .save__check-bar {
    animation: none !important;
  }
  .save.is-saved .save__ring {
    opacity: 1;
    transform: scale(1);
  }
  .save.is-saved .save__disk {
    opacity: 0;
  }
  .save.is-saved .save__check-bar--short {
    transform: rotate(225deg) scaleX(1);
  }
  .save.is-saved .save__check-bar--long {
    transform: rotate(-52deg) scaleX(1);
  }
}

// 실제 클릭 한 번 = Save 완료 한 번. 데모(.is-demo) 루프는 손을 대면 멈추고 수동 상태로 바뀐다.
document.querySelector('.save').addEventListener('click', function (e) {
  var b = e.currentTarget;
  b.classList.remove('is-demo');
  b.classList.remove('is-saved');
  void b.offsetWidth;
  b.classList.add('is-saved');
});

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

export type SaveCheckButtonProps = {
  label: string;
  /** 디스켓 → 체크 전환 시간 (기본 300ms) */
  duration?: number;
  easing?: string;
  /** 완료 배지 강조색 */
  color?: string;
  onSave?: (e: MouseEvent<HTMLButtonElement>) => void;
};

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

export default function SaveCheckButton({
  label,
  duration = 300,
  easing = "cubic-bezier(.2,1.4,.4,1)",
  color = "#2f6df6",
  onSave,
}: SaveCheckButtonProps) {
  const [saved, setSaved] = useState(false);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  const handle = (e: MouseEvent<HTMLButtonElement>) => {
    setSaved(true);
    onSave?.(e);
  };

  return (
    <button
      type="button"
      className={saved ? `${styles.save} ${styles.saved}` : styles.save}
      style={vars}
      onClick={handle}
    >
      <span className={styles.icon} aria-hidden="true">
        <span className={styles.ring} />
        <span className={styles.disk} />
        <span className={styles.check}>
          <span className={`${styles.bar} ${styles.barShort}`} />
          <span className={`${styles.bar} ${styles.barLong}`} />
        </span>
      </span>
      <span>{label}</span>
    </button>
  );
}