05ブロブモーフィング

<main class="stage">
  <span class="blob m1" aria-hidden="true"></span>
  <span class="blob m2" aria-hidden="true"></span>
  <span class="blob m3" aria-hidden="true"></span>
  <p class="hint">空状態</p>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-loop;                                // 세 블롭이 한 바퀴 교차하는 시간
$easing: $ease-spring;
$color: $subject-cream;                               // 블롭 색

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

.stage {
  position: relative;
  overflow: hidden;
}

// border-radius 는 세 블롭마다 고정값. opacity·transform 만 움직여 border-radius 를 매 프레임 다시 계산하지 않는다
.blob {
  position: absolute;
  width: 52%;
  aspect-ratio: 1;
  left: 24%;
  top: 18%;
  background: $color;
}

.m1 { border-radius: 42% 58% 63% 37% / 41% 44% 56% 59%; animation: morph1 $duration $easing infinite; }
.m2 { border-radius: 63% 37% 41% 59% / 55% 48% 52% 45%; opacity: 0; animation: morph2 $duration $easing infinite; }
.m3 { border-radius: 35% 65% 55% 45% / 60% 40% 60% 40%; opacity: 0; animation: morph3 $duration $easing infinite; }

@keyframes morph1 {
  0%   { opacity: 1; transform: scale(1) rotate(0deg); }
  28%  { opacity: 1; transform: scale(1.05) rotate(4deg); }
  38%  { opacity: 0; transform: scale(.94) rotate(8deg); }
  92%  { opacity: 0; }
  100% { opacity: 1; transform: scale(1) rotate(0deg); }
}
@keyframes morph2 {
  0%, 30% { opacity: 0; }
  40%  { opacity: 1; transform: scale(1) rotate(0deg); }
  68%  { opacity: 1; transform: scale(1.05) rotate(-4deg); }
  78%  { opacity: 0; transform: scale(.94) rotate(-8deg); }
  100% { opacity: 0; }
}
@keyframes morph3 {
  0%, 70% { opacity: 0; }
  80%  { opacity: 1; transform: scale(1) rotate(0deg); }
  96%  { opacity: 1; transform: scale(1.05) rotate(4deg); }
  100% { opacity: 0; }
}

.hint {
  position: relative;
  margin: 0;
  padding: 10px 20px;
  border-radius: $r-pill;
  background: $subject-cream;
  color: $subject-ink;
  font: 700 clamp(14px, 4vw, 18px)/1.3 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

@media (prefers-reduced-motion: reduce) {
  .blob { animation: none; }
  .m1 { opacity: 1; }
  .m2, .m3 { opacity: 0; }
}

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);
}

.stage {
  position: relative;
  overflow: hidden;
}

.blob {
  position: absolute;
  width: 52%;
  aspect-ratio: 1;
  left: 24%;
  top: 18%;
  background: #fff7e6;
}

.m1 {
  border-radius: 42% 58% 63% 37%/41% 44% 56% 59%;
  animation: morph1 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.m2 {
  border-radius: 63% 37% 41% 59%/55% 48% 52% 45%;
  opacity: 0;
  animation: morph2 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.m3 {
  border-radius: 35% 65% 55% 45%/60% 40% 60% 40%;
  opacity: 0;
  animation: morph3 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes morph1 {
  0% {
    opacity: 1;
    transform: scale(1) rotate(0deg);
  }
  28% {
    opacity: 1;
    transform: scale(1.05) rotate(4deg);
  }
  38% {
    opacity: 0;
    transform: scale(0.94) rotate(8deg);
  }
  92% {
    opacity: 0;
  }
  100% {
    opacity: 1;
    transform: scale(1) rotate(0deg);
  }
}
@keyframes morph2 {
  0%, 30% {
    opacity: 0;
  }
  40% {
    opacity: 1;
    transform: scale(1) rotate(0deg);
  }
  68% {
    opacity: 1;
    transform: scale(1.05) rotate(-4deg);
  }
  78% {
    opacity: 0;
    transform: scale(0.94) rotate(-8deg);
  }
  100% {
    opacity: 0;
  }
}
@keyframes morph3 {
  0%, 70% {
    opacity: 0;
  }
  80% {
    opacity: 1;
    transform: scale(1) rotate(0deg);
  }
  96% {
    opacity: 1;
    transform: scale(1.05) rotate(4deg);
  }
  100% {
    opacity: 0;
  }
}
.hint {
  position: relative;
  margin: 0;
  padding: 10px 20px;
  border-radius: 999px;
  background: #fff7e6;
  color: #17141a;
  font: 700 clamp(14px, 4vw, 18px)/1.3 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

@media (prefers-reduced-motion: reduce) {
  .blob {
    animation: none;
  }
  .m1 {
    opacity: 1;
  }
  .m2, .m3 {
    opacity: 0;
  }
}

import type { CSSProperties, ReactNode } from "react";
import styles from "./BlobMorphBg.module.scss";

export type BlobMorphBgProps = {
  children?: ReactNode;
  /** 세 블롭이 한 바퀴 교차하는 시간 (기본 2000ms) */
  duration?: number;
  easing?: string;
  /** 블롭 색 */
  color?: string;
  className?: string;
};

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

export default function BlobMorphBg({
  children,
  duration = 2000,
  easing = "cubic-bezier(.2,.8,.2,1)",
  color = "#fff7e6",
  className = "",
}: BlobMorphBgProps) {
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };
  return (
    <div className={`${styles.stage} ${className}`} style={vars}>
      <span className={`${styles.blob} ${styles.m1}`} aria-hidden="true" />
      <span className={`${styles.blob} ${styles.m2}`} aria-hidden="true" />
      <span className={`${styles.blob} ${styles.m3}`} aria-hidden="true" />
      {children}
    </div>
  );
}