02Curtain split reveal

<main class="stage">
  <div class="cs-frame cs-focal is-demo">
    <div class="cs-photo"></div>
    <div class="cs-panel cs-panel--l"></div>
    <div class="cs-panel cs-panel--r"></div>
  </div>
</main>

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

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

@include stage($stage-yellow);

.cs-frame {
  position: relative;
  width: min(260px, 78vw);
  aspect-ratio: 8 / 5;
  border-radius: $r-card;
  overflow: hidden;
  box-shadow: $shadow-raised;
}

.cs-photo {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(110px circle at 30% 70%, rgba(255, 255, 255, .5), transparent 58%),
    linear-gradient(135deg, $subject-blue, $subject-cream 130%);
}

.cs-panel {
  position: absolute;
  top: 0; bottom: 0;
  width: 50%;
  background: $color;
}
.cs-panel--l { left: 0; transform: translateX(0); }
.cs-panel--r { left: 50%; transform: translateX(0); }

// 실사용: 진짜 마우스 호버 — 왼쪽은 왼쪽으로, 오른쪽은 오른쪽으로 밀려나며 커튼처럼 열린다
.cs-panel { transition: transform $duration $easing; }
.cs-focal:hover .cs-panel--l { transform: translateX(-100%); }
.cs-focal:hover .cs-panel--r { transform: translateX(100%); }

// 데모 루프
@keyframes cs-open-l {
  0%, 8%   { transform: translateX(0); }
  45%, 60% { transform: translateX(-100%); }
  95%, 100% { transform: translateX(0); }
}
@keyframes cs-open-r {
  0%, 8%   { transform: translateX(0); }
  45%, 60% { transform: translateX(100%); }
  95%, 100% { transform: translateX(0); }
}
.cs-frame.is-demo .cs-panel--l { animation: cs-open-l $dur-loop $easing infinite; }
.cs-frame.is-demo .cs-panel--r { animation: cs-open-r $dur-loop $easing infinite; }

@media (prefers-reduced-motion: reduce) {
  .cs-focal:hover .cs-panel--l, .cs-frame.is-demo .cs-panel--l { animation: none !important; transition: none !important; transform: translateX(-100%) !important; }
  .cs-focal:hover .cs-panel--r, .cs-frame.is-demo .cs-panel--r { animation: none !important; transition: none !important; transform: translateX(100%) !important; }
}

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);
}

.cs-frame {
  position: relative;
  width: min(260px, 78vw);
  aspect-ratio: 8/5;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
}

.cs-photo {
  position: absolute;
  inset: 0;
  background: radial-gradient(110px circle at 30% 70%, rgba(255, 255, 255, 0.5), transparent 58%), linear-gradient(135deg, #2f6df6, #fff7e6 130%);
}

.cs-panel {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 50%;
  background: #17141a;
}

.cs-panel--l {
  left: 0;
  transform: translateX(0);
}

.cs-panel--r {
  left: 50%;
  transform: translateX(0);
}

.cs-panel {
  transition: transform 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.cs-focal:hover .cs-panel--l {
  transform: translateX(-100%);
}

.cs-focal:hover .cs-panel--r {
  transform: translateX(100%);
}

@keyframes cs-open-l {
  0%, 8% {
    transform: translateX(0);
  }
  45%, 60% {
    transform: translateX(-100%);
  }
  95%, 100% {
    transform: translateX(0);
  }
}
@keyframes cs-open-r {
  0%, 8% {
    transform: translateX(0);
  }
  45%, 60% {
    transform: translateX(100%);
  }
  95%, 100% {
    transform: translateX(0);
  }
}
.cs-frame.is-demo .cs-panel--l {
  animation: cs-open-l 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.cs-frame.is-demo .cs-panel--r {
  animation: cs-open-r 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@media (prefers-reduced-motion: reduce) {
  .cs-focal:hover .cs-panel--l, .cs-frame.is-demo .cs-panel--l {
    animation: none !important;
    transition: none !important;
    transform: translateX(-100%) !important;
  }
  .cs-focal:hover .cs-panel--r, .cs-frame.is-demo .cs-panel--r {
    animation: none !important;
    transition: none !important;
    transform: translateX(100%) !important;
  }
}

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

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

export interface CurtainSplitProps {
  duration?: string;
  easing?: string;
  color?: string;
}

export default function CurtainSplit({
  duration = "600ms",
  easing = "cubic-bezier(.2, .8, .2, 1)",
  color = "#17141a",
}: CurtainSplitProps) {
  const style: Vars = {
    "--duration": duration,
    "--easing": easing,
    "--color": color,
  };
  return (
    <div className={styles.frame} style={style}>
      <div className={styles.photo} />
      <div className={`${styles.panel} ${styles.panelL}`} />
      <div className={`${styles.panel} ${styles.panelR}`} />
    </div>
  );
}