09Stacked modals

<main class="stage is-demo">
  <div class="overlay"></div>
  <div class="modal modal--1" role="dialog" aria-modal="true" aria-labelledby="t9a">
    <h2 id="t9a">Enter shipping address</h2>
    <p>Enter your address, then look up the postal code.</p>
    <button class="modal__next" type="button">Look up postal code</button>
  </div>
  <div class="modal modal--2" role="dialog" aria-modal="true" aria-labelledby="t9b">
    <h2 id="t9b">Look up postal code</h2>
    <p>Searching by street name is faster.</p>
    <button class="modal__back" type="button">Use this address</button>
  </div>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-enter;     // 두 번째 모달이 뜨는 시간
$easing: $ease-spring;
$color: $subject-blue;     // 강조색(버튼)

@include stage($stage-ink);

.stage { position: relative; }

.overlay {
  position: fixed; inset: 0;
  background: rgba($stage-ink, .35);
  transition: background $duration $easing;
}

.modal {
  position: fixed; left: 50%; top: 50%;
  width: min(78vw, 300px);
  padding: clamp(12px, 4.5vmin, 22px);
  border-radius: $r-card; background: $stage-paper; color: $stage-ink;
  box-shadow: $shadow-raised;

  h2 { margin: 0 0 6px; font-size: clamp(13px, 4.2vmin, 17px); }
  p  { margin: 0 0 14px; font-size: clamp(10px, 3.2vmin, 13px); color: rgba($stage-ink, .65); }
}

.modal__next, .modal__back {
  border: 0; border-radius: $r-control; background: $color; color: $stage-paper;
  padding: clamp(7px, 2.6vmin, 9px) clamp(14px, 4.6vmin, 18px);
  font-weight: 600;
  font-size: clamp(11px, 3.4vmin, 13px);
  line-height: 1;
  font-family: inherit;
  cursor: pointer;
}

// 1번 모달: 평소엔 정면, 2번이 열리면 뒤로 물러나 작아진다
.modal--1 {
  transform: translate(-50%, -50%);
  transition: transform $duration $easing, opacity $duration $easing;
}
// 2번 모달: 평소엔 숨어 있다가 열리면 앞으로
.modal--2 {
  transform: translate(-50%, -50%) translateY(10px) scale(.9);
  opacity: 0; pointer-events: none;
  transition: transform $duration $easing, opacity $duration $easing;
}

.stage.is-stacked .overlay { background: rgba($stage-ink, .6); }
.stage.is-stacked .modal--1 { transform: translate(-50%, calc(-50% - 16px)) scale(.95); opacity: .55; }
.stage.is-stacked .modal--2 { transform: translate(-50%, -50%) translateY(0) scale(1); opacity: 1; pointer-events: auto; }

.stage.is-demo .overlay      { animation: overlay-loop $dur-loop ease-in-out infinite; }
.stage.is-demo .modal--1     { animation: back-loop $dur-loop $easing infinite; }
.stage.is-demo .modal--2     { animation: front-loop $dur-loop $easing infinite; }

@keyframes overlay-loop {
  0%, 40%   { background: rgba($stage-ink, .35); }
  55%, 80%  { background: rgba($stage-ink, .6); }
  95%, 100% { background: rgba($stage-ink, .35); }
}
@keyframes back-loop {
  0%, 40%   { transform: translate(-50%, -50%) scale(1); opacity: 1; }
  55%, 80%  { transform: translate(-50%, calc(-50% - 16px)) scale(.95); opacity: .55; }
  95%, 100% { transform: translate(-50%, -50%) scale(1); opacity: 1; }
}
@keyframes front-loop {
  0%, 40%   { transform: translate(-50%, -50%) translateY(10px) scale(.9); opacity: 0; }
  55%, 80%  { transform: translate(-50%, -50%) translateY(0) scale(1); opacity: 1; }
  95%, 100% { transform: translate(-50%, -50%) translateY(10px) scale(.9); opacity: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .overlay, .stage.is-demo .modal--1, .stage.is-demo .modal--2 { animation: none; }
  .overlay, .modal--1, .modal--2 { transition-duration: 1ms; }
}

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;
}

.overlay {
  position: fixed;
  inset: 0;
  background: rgba(23, 20, 26, 0.35);
  transition: background 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.modal {
  position: fixed;
  left: 50%;
  top: 50%;
  width: min(78vw, 300px);
  padding: clamp(12px, 4.5vmin, 22px);
  border-radius: 16px;
  background: #ffffff;
  color: #17141a;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
}
.modal h2 {
  margin: 0 0 6px;
  font-size: clamp(13px, 4.2vmin, 17px);
}
.modal p {
  margin: 0 0 14px;
  font-size: clamp(10px, 3.2vmin, 13px);
  color: rgba(23, 20, 26, 0.65);
}

.modal__next, .modal__back {
  border: 0;
  border-radius: 12px;
  background: #2f6df6;
  color: #ffffff;
  padding: clamp(7px, 2.6vmin, 9px) clamp(14px, 4.6vmin, 18px);
  font-weight: 600;
  font-size: clamp(11px, 3.4vmin, 13px);
  line-height: 1;
  font-family: inherit;
  cursor: pointer;
}

.modal--1 {
  transform: translate(-50%, -50%);
  transition: transform 600ms cubic-bezier(0.2, 0.8, 0.2, 1), opacity 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.modal--2 {
  transform: translate(-50%, -50%) translateY(10px) scale(0.9);
  opacity: 0;
  pointer-events: none;
  transition: transform 600ms cubic-bezier(0.2, 0.8, 0.2, 1), opacity 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.stage.is-stacked .overlay {
  background: rgba(23, 20, 26, 0.6);
}

.stage.is-stacked .modal--1 {
  transform: translate(-50%, calc(-50% - 16px)) scale(0.95);
  opacity: 0.55;
}

.stage.is-stacked .modal--2 {
  transform: translate(-50%, -50%) translateY(0) scale(1);
  opacity: 1;
  pointer-events: auto;
}

.stage.is-demo .overlay {
  animation: overlay-loop 2s ease-in-out infinite;
}

.stage.is-demo .modal--1 {
  animation: back-loop 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.stage.is-demo .modal--2 {
  animation: front-loop 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes overlay-loop {
  0%, 40% {
    background: rgba(23, 20, 26, 0.35);
  }
  55%, 80% {
    background: rgba(23, 20, 26, 0.6);
  }
  95%, 100% {
    background: rgba(23, 20, 26, 0.35);
  }
}
@keyframes back-loop {
  0%, 40% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
  }
  55%, 80% {
    transform: translate(-50%, calc(-50% - 16px)) scale(0.95);
    opacity: 0.55;
  }
  95%, 100% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
  }
}
@keyframes front-loop {
  0%, 40% {
    transform: translate(-50%, -50%) translateY(10px) scale(0.9);
    opacity: 0;
  }
  55%, 80% {
    transform: translate(-50%, -50%) translateY(0) scale(1);
    opacity: 1;
  }
  95%, 100% {
    transform: translate(-50%, -50%) translateY(10px) scale(0.9);
    opacity: 0;
  }
}
@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .overlay, .stage.is-demo .modal--1, .stage.is-demo .modal--2 {
    animation: none;
  }
  .overlay, .modal--1, .modal--2 {
    transition-duration: 1ms;
  }
}

(function () {
  var stage = document.querySelector('.stage');
  var next = document.querySelector('.modal__next');
  var back = document.querySelector('.modal__back');
  next.addEventListener('click', function () { stage.classList.remove('is-demo'); stage.classList.add('is-stacked'); });
  back.addEventListener('click', function () { stage.classList.remove('is-stacked'); });
})();

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

export type StackedModalsProps = {
  firstTitle: string;
  firstDescription: string;
  nextLabel: string;
  secondTitle: string;
  secondDescription: string;
  backLabel: string;
  /** 두 번째 모달이 뜨는 시간 (기본 600ms) */
  duration?: number;
  easing?: string;
  color?: string;
};

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

export default function StackedModals({
  firstTitle,
  firstDescription,
  nextLabel,
  secondTitle,
  secondDescription,
  backLabel,
  duration = 600,
  easing = "cubic-bezier(.2,.8,.2,1)",
  color = "#2f6df6",
}: StackedModalsProps) {
  const [stacked, setStacked] = useState(false);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <div className={styles.stage} style={vars}>
      <div className={stacked ? `${styles.overlay} ${styles.isStacked}` : styles.overlay} />
      <div className={stacked ? `${styles.modal} ${styles.back}` : styles.modal}>
        <h2>{firstTitle}</h2>
        <p>{firstDescription}</p>
        <button type="button" className={styles.next} onClick={() => setStacked(true)}>
          {nextLabel}
        </button>
      </div>
      <div className={stacked ? `${styles.modal2} ${styles.isOpen}` : styles.modal2}>
        <h2>{secondTitle}</h2>
        <p>{secondDescription}</p>
        <button type="button" className={styles.back2} onClick={() => setStacked(false)}>
          {backLabel}
        </button>
      </div>
    </div>
  );
}