09Coverflow 3D

<main class="stage">
  <div class="cf is-demo">
    <input type="radio" name="cf-tab" id="cf-1" class="cf__radio" checked>
    <input type="radio" name="cf-tab" id="cf-2" class="cf__radio">
    <input type="radio" name="cf-tab" id="cf-3" class="cf__radio">
    <div class="cf__stage">
      <label class="cf__slide cf__slide--1" for="cf-1" aria-label="Slide 1"></label>
      <label class="cf__slide cf__slide--2" for="cf-2" aria-label="Slide 2"></label>
      <label class="cf__slide cf__slide--3" for="cf-3" aria-label="Slide 3"></label>
    </div>
  </div>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-enter;
$easing: $ease-spring;
$color: $subject-blue;

@include stage($stage-ink);

.cf { width: min(400px, 92vw); }
.cf__radio { position: absolute; opacity: 0; pointer-events: none; }

.cf__stage {
  position: relative;
  height: clamp(140px, 44vw, 200px);
  perspective: 720px;
}
.cf__slide {
  position: absolute;
  top: 0; left: 50%;
  width: 46%;
  height: 100%;
  margin-left: -23%;
  border-radius: $r-card;
  cursor: pointer;
  transform-style: preserve-3d;
  transition: transform $duration $easing, opacity $duration $easing;
}
.cf__slide--1 { background: linear-gradient(160deg, $color, #d6ddeb); }
.cf__slide--2 { background: linear-gradient(160deg, $stage-orange, #ebdbd6); }
.cf__slide--3 { background: linear-gradient(160deg, #c2ae82, $stage-yellow); }
.cf__slide::before {
  content: ""; position: absolute; top: $sp-3; right: $sp-3;
  width: $sp-6; height: $sp-6; border-radius: 50%;
  background: rgba(255, 255, 255, .85);
}
.cf__slide::after {
  content: ""; position: absolute; left: -10%; right: -10%; bottom: -6%; height: 46%;
  background: rgba(23, 20, 26, .26);
  clip-path: polygon(0% 100%, 22% 40%, 42% 66%, 60% 26%, 78% 60%, 100% 34%, 100% 100%);
}

// ── 실제 동작: 고른 라디오의 슬라이드가 정면 중앙으로, 나머지 둘은 좌우로 기울어 물러난다 ──
$center: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
$prev:   translateX(-108%) translateZ(-120px) rotateY(38deg) scale(.74);
$next:   translateX(8%) translateZ(-120px) rotateY(-38deg) scale(.74);

#cf-1:checked ~ .cf__stage .cf__slide--1 { transform: $center; z-index: 2; }
#cf-1:checked ~ .cf__stage .cf__slide--2 { transform: $next; z-index: 1; opacity: .7; }
#cf-1:checked ~ .cf__stage .cf__slide--3 { transform: $prev; z-index: 1; opacity: .7; }
#cf-2:checked ~ .cf__stage .cf__slide--2 { transform: $center; z-index: 2; }
#cf-2:checked ~ .cf__stage .cf__slide--3 { transform: $next; z-index: 1; opacity: .7; }
#cf-2:checked ~ .cf__stage .cf__slide--1 { transform: $prev; z-index: 1; opacity: .7; }
#cf-3:checked ~ .cf__stage .cf__slide--3 { transform: $center; z-index: 2; }
#cf-3:checked ~ .cf__stage .cf__slide--1 { transform: $next; z-index: 1; opacity: .7; }
#cf-3:checked ~ .cf__stage .cf__slide--2 { transform: $prev; z-index: 1; opacity: .7; }

// ── 데모 루프: 클릭 전까지 세 장이 스스로 중앙 자리를 돌아가며 맡는다 ──
.cf.is-demo .cf__slide--1 { animation: cf-1 $dur-loop $easing infinite; }
.cf.is-demo .cf__slide--2 { animation: cf-2 $dur-loop $easing infinite; }
.cf.is-demo .cf__slide--3 { animation: cf-3 $dur-loop $easing infinite; }
@keyframes cf-1 {
  0%, 4%    { transform: $center; opacity: 1; }
  29%, 62%  { transform: $next; opacity: .7; }
  66%, 96%  { transform: $prev; opacity: .7; }
  100%      { transform: $center; opacity: 1; }
}
@keyframes cf-2 {
  0%, 29%   { transform: $prev; opacity: .7; }
  33%, 62%  { transform: $center; opacity: 1; }
  66%, 96%  { transform: $next; opacity: .7; }
  100%      { transform: $prev; opacity: .7; }
}
@keyframes cf-3 {
  0%, 29%   { transform: $next; opacity: .7; }
  33%, 62%  { transform: $prev; opacity: .7; }
  66%, 96%  { transform: $center; opacity: 1; }
  100%      { transform: $next; opacity: .7; }
}

// ── 접근성 ──────────────────────────────────────────
@media (prefers-reduced-motion: reduce) {
  .cf__slide { transition: none; }
  .cf.is-demo .cf__slide--1,
  .cf.is-demo .cf__slide--2,
  .cf.is-demo .cf__slide--3 { 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: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.cf {
  width: min(400px, 92vw);
}

.cf__radio {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.cf__stage {
  position: relative;
  height: clamp(140px, 44vw, 200px);
  perspective: 720px;
}

.cf__slide {
  position: absolute;
  top: 0;
  left: 50%;
  width: 46%;
  height: 100%;
  margin-left: -23%;
  border-radius: 16px;
  cursor: pointer;
  transform-style: preserve-3d;
  transition: transform 600ms cubic-bezier(0.2, 0.8, 0.2, 1), opacity 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.cf__slide--1 {
  background: linear-gradient(160deg, #2f6df6, #d6ddeb);
}

.cf__slide--2 {
  background: linear-gradient(160deg, #ff4d1f, #ebdbd6);
}

.cf__slide--3 {
  background: linear-gradient(160deg, #c2ae82, #ffd23f);
}

.cf__slide::before {
  content: "";
  position: absolute;
  top: 12px;
  right: 12px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.85);
}

.cf__slide::after {
  content: "";
  position: absolute;
  left: -10%;
  right: -10%;
  bottom: -6%;
  height: 46%;
  background: rgba(23, 20, 26, 0.26);
  clip-path: polygon(0% 100%, 22% 40%, 42% 66%, 60% 26%, 78% 60%, 100% 34%, 100% 100%);
}

#cf-1:checked ~ .cf__stage .cf__slide--1 {
  transform: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
  z-index: 2;
}

#cf-1:checked ~ .cf__stage .cf__slide--2 {
  transform: translateX(8%) translateZ(-120px) rotateY(-38deg) scale(0.74);
  z-index: 1;
  opacity: 0.7;
}

#cf-1:checked ~ .cf__stage .cf__slide--3 {
  transform: translateX(-108%) translateZ(-120px) rotateY(38deg) scale(0.74);
  z-index: 1;
  opacity: 0.7;
}

#cf-2:checked ~ .cf__stage .cf__slide--2 {
  transform: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
  z-index: 2;
}

#cf-2:checked ~ .cf__stage .cf__slide--3 {
  transform: translateX(8%) translateZ(-120px) rotateY(-38deg) scale(0.74);
  z-index: 1;
  opacity: 0.7;
}

#cf-2:checked ~ .cf__stage .cf__slide--1 {
  transform: translateX(-108%) translateZ(-120px) rotateY(38deg) scale(0.74);
  z-index: 1;
  opacity: 0.7;
}

#cf-3:checked ~ .cf__stage .cf__slide--3 {
  transform: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
  z-index: 2;
}

#cf-3:checked ~ .cf__stage .cf__slide--1 {
  transform: translateX(8%) translateZ(-120px) rotateY(-38deg) scale(0.74);
  z-index: 1;
  opacity: 0.7;
}

#cf-3:checked ~ .cf__stage .cf__slide--2 {
  transform: translateX(-108%) translateZ(-120px) rotateY(38deg) scale(0.74);
  z-index: 1;
  opacity: 0.7;
}

.cf.is-demo .cf__slide--1 {
  animation: cf-1 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.cf.is-demo .cf__slide--2 {
  animation: cf-2 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.cf.is-demo .cf__slide--3 {
  animation: cf-3 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes cf-1 {
  0%, 4% {
    transform: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
    opacity: 1;
  }
  29%, 62% {
    transform: translateX(8%) translateZ(-120px) rotateY(-38deg) scale(0.74);
    opacity: 0.7;
  }
  66%, 96% {
    transform: translateX(-108%) translateZ(-120px) rotateY(38deg) scale(0.74);
    opacity: 0.7;
  }
  100% {
    transform: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
    opacity: 1;
  }
}
@keyframes cf-2 {
  0%, 29% {
    transform: translateX(-108%) translateZ(-120px) rotateY(38deg) scale(0.74);
    opacity: 0.7;
  }
  33%, 62% {
    transform: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
    opacity: 1;
  }
  66%, 96% {
    transform: translateX(8%) translateZ(-120px) rotateY(-38deg) scale(0.74);
    opacity: 0.7;
  }
  100% {
    transform: translateX(-108%) translateZ(-120px) rotateY(38deg) scale(0.74);
    opacity: 0.7;
  }
}
@keyframes cf-3 {
  0%, 29% {
    transform: translateX(8%) translateZ(-120px) rotateY(-38deg) scale(0.74);
    opacity: 0.7;
  }
  33%, 62% {
    transform: translateX(-108%) translateZ(-120px) rotateY(38deg) scale(0.74);
    opacity: 0.7;
  }
  66%, 96% {
    transform: translateX(-50%) translateZ(0) rotateY(0deg) scale(1);
    opacity: 1;
  }
  100% {
    transform: translateX(8%) translateZ(-120px) rotateY(-38deg) scale(0.74);
    opacity: 0.7;
  }
}
@media (prefers-reduced-motion: reduce) {
  .cf__slide {
    transition: none;
  }
  .cf.is-demo .cf__slide--1,
  .cf.is-demo .cf__slide--2,
  .cf.is-demo .cf__slide--3 {
    animation: none !important;
  }
}

// 실제 동작은 :checked 만으로 끝난다(0줄). 이 3줄은 미리보기 자동 재생만 멈춘다.
document.querySelectorAll('.cf__radio').forEach(function (r) {
  r.addEventListener('pointerdown', function () { document.querySelector('.cf').classList.remove('is-demo'); });
});

import { useState } from "react";
import type { CSSProperties } from "react";
import styles from "./Coverflow3d.module.scss";

export type Coverflow3dProps = {
  duration?: number;
  easing?: string;
  color?: string;
};

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

function roleOf(i: number, active: number, n: number): "center" | "prev" | "next" {
  if (i === active) return "center";
  return (i - active + n) % n === 1 ? "next" : "prev";
}

export default function Coverflow3d({ duration = 600, easing = "cubic-bezier(.2,.8,.2,1)", color = "#2f6df6" }: Coverflow3dProps) {
  const [active, setActive] = useState(0);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };
  const n = 3;
  return (
    <div className={styles.cf} style={vars}>
      <div className={styles.stageBox}>
        {[0, 1, 2].map((i) => (
          <button
            key={i}
            type="button"
            aria-label={`슬라이드 ${i + 1}`}
            className={`${styles.slide} ${styles["slide" + (i + 1)]} ${styles[roleOf(i, active, n)]}`}
            onClick={() => setActive(i)}
          />
        ))}
      </div>
    </div>
  );
}