07Ripple ring button

<main class="stage is-demo">
  <button class="btn" type="button" aria-label="Like">
    <svg class="btn__heart" viewBox="0 0 256 256" aria-hidden="true" focusable="false">
      <g fill="currentColor"><path d="M232 102c0 66-104 122-104 122S24 168 24 102a54 54 0 0 1 54-54c22.59 0 41.94 12.31 50 32c8.06-19.69 27.41-32 50-32a54 54 0 0 1 54 54" opacity=".2"/><path d="M178 40c-20.65 0-38.73 8.88-50 23.89C116.73 48.88 98.65 40 78 40a62.07 62.07 0 0 0-62 62c0 70 103.79 126.66 108.21 129a8 8 0 0 0 7.58 0C136.21 228.66 240 172 240 102a62.07 62.07 0 0 0-62-62m-50 174.8c-18.26-10.64-96-59.11-96-112.8a46.06 46.06 0 0 1 46-46c19.45 0 35.78 10.36 42.6 27a8 8 0 0 0 14.8 0c6.82-16.67 23.15-27 42.6-27a46.06 46.06 0 0 1 46 46c0 53.61-77.76 102.15-96 112.8"/></g>
    </svg>
  </button>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-loop;     // 2s — 핑 두 번
$easing: $ease-out;
$color: $subject-blue;    // 링·하트 색

@include stage($stage-orange);

.btn {
  box-sizing: border-box;
  position: relative;
  width: 112px;
  height: 112px;
  border: none;
  border-radius: 50%;
  background: $stage-paper;
  cursor: pointer;
  display: grid;
  place-items: center;
  box-shadow: $shadow-raised;
}

.btn__heart {
  width: 44px;
  height: 44px;
  color: $color;   // Phosphor duotone: g fill="currentColor" 가 이 값을 물려받는다
}

// 테두리 링 — 채워진 원이 아니라 굵은 선이 퍼진다
.btn::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 3px solid $color;
  opacity: 0;
  transform: scale(1);
}

// 실사용: 누르는 순간 한 번
.btn:active .btn__heart { animation: heart-pop $dur-base $ease-pop 1; }
.btn:active::after { animation: ring $dur-base $easing 1; }

.btn:focus-visible { outline: 3px solid $subject-ink; outline-offset: 4px; }

// 격자 미리보기: 2초에 두 번 종소리처럼 퍼진다
.stage.is-demo .btn__heart { animation: heart-pop $duration $ease-pop infinite; }
.stage.is-demo .btn::after { animation: ring $duration $easing infinite; }

@keyframes ring {
  0%   { transform: scale(1);   opacity: .9; }
  34%  { transform: scale(1.8); opacity: 0; }
  50%  { transform: scale(1);   opacity: .9; }
  84%  { transform: scale(1.8); opacity: 0; }
  100% { transform: scale(1);   opacity: 0; }
}
@keyframes heart-pop {
  0%, 50%  { transform: scale(1); }
  8%, 58%  { transform: scale(1.14); }
  16%, 66% { transform: scale(.96); }
  22%, 72% { transform: scale(1); }
}

@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .btn__heart, .stage.is-demo .btn::after { animation: none; }
  .stage.is-demo .btn::after { opacity: 0; }
}

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);
}

.btn {
  box-sizing: border-box;
  position: relative;
  width: 112px;
  height: 112px;
  border: none;
  border-radius: 50%;
  background: #ffffff;
  cursor: pointer;
  display: grid;
  place-items: center;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
}

.btn__heart {
  width: 44px;
  height: 44px;
  color: #2f6df6;
}

.btn::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 3px solid #2f6df6;
  opacity: 0;
  transform: scale(1);
}

.btn:active .btn__heart {
  animation: heart-pop 300ms cubic-bezier(0.2, 1.4, 0.4, 1) 1;
}

.btn:active::after {
  animation: ring 300ms ease-out 1;
}

.btn:focus-visible {
  outline: 3px solid #17141a;
  outline-offset: 4px;
}

.stage.is-demo .btn__heart {
  animation: heart-pop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

.stage.is-demo .btn::after {
  animation: ring 2s ease-out infinite;
}

@keyframes ring {
  0% {
    transform: scale(1);
    opacity: 0.9;
  }
  34% {
    transform: scale(1.8);
    opacity: 0;
  }
  50% {
    transform: scale(1);
    opacity: 0.9;
  }
  84% {
    transform: scale(1.8);
    opacity: 0;
  }
  100% {
    transform: scale(1);
    opacity: 0;
  }
}
@keyframes heart-pop {
  0%, 50% {
    transform: scale(1);
  }
  8%, 58% {
    transform: scale(1.14);
  }
  16%, 66% {
    transform: scale(0.96);
  }
  22%, 72% {
    transform: scale(1);
  }
}
@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .btn__heart, .stage.is-demo .btn::after {
    animation: none;
  }
  .stage.is-demo .btn::after {
    opacity: 0;
  }
}

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

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

export default function RippleRingButton({
  duration = 300,
  easing = "ease-out",
  color = "#2f6df6",
  label = "좋아요",
}: RippleRingButtonProps) {
  const vars: CSSProperties = { "--duration": `${duration}ms`, "--easing": easing, "--color": color } as CSSProperties;
  return (
    <button className={styles.btn} style={vars} type="button" aria-label={label}>
      <svg className={styles.heart} viewBox="0 0 256 256" aria-hidden="true" focusable="false">
        <g fill="currentColor"><path d="M232 102c0 66-104 122-104 122S24 168 24 102a54 54 0 0 1 54-54c22.59 0 41.94 12.31 50 32c8.06-19.69 27.41-32 50-32a54 54 0 0 1 54 54" opacity=".2" /><path d="M178 40c-20.65 0-38.73 8.88-50 23.89C116.73 48.88 98.65 40 78 40a62.07 62.07 0 0 0-62 62c0 70 103.79 126.66 108.21 129a8 8 0 0 0 7.58 0C136.21 228.66 240 172 240 102a62.07 62.07 0 0 0-62-62m-50 174.8c-18.26-10.64-96-59.11-96-112.8a46.06 46.06 0 0 1 46-46c19.45 0 35.78 10.36 42.6 27a8 8 0 0 0 14.8 0c6.82-16.67 23.15-27 42.6-27a46.06 46.06 0 0 1 46 46c0 53.61-77.76 102.15-96 112.8" /></g>
      </svg>
    </button>
  );
}