08손가락으로 넘기는 플랜 카드

<main class="stage">
  <div class="sw is-demo" role="group" aria-label="플랜 넘기기">
    <div class="sw__view" id="sw-view">
      <div class="sw__track" id="sw-track">
        <article class="sw__card">
          <div class="sw__inner">
            <p class="sw__name"><span class="sw__nametext">스타터</span></p>
            <p class="sw__price"><span class="sw__amt">$9</span><span class="sw__per">/ 월</span></p>
            <ul class="sw__list">
              <li>프로젝트 무제한</li>
              <li>팀원 초대</li>
            </ul>
          </div>
        </article>
        <article class="sw__card">
          <div class="sw__inner">
            <p class="sw__name"><span class="sw__nametext">프로</span><span class="sw__tag">추천</span></p>
            <p class="sw__price"><span class="sw__amt">$29</span><span class="sw__per">/ 월</span></p>
            <ul class="sw__list">
              <li>우선 지원</li>
              <li>팀원 초대</li>
            </ul>
          </div>
        </article>
        <article class="sw__card">
          <div class="sw__inner">
            <p class="sw__name"><span class="sw__nametext">비즈니스</span></p>
            <p class="sw__price"><span class="sw__amt">$79</span><span class="sw__per">/ 월</span></p>
            <ul class="sw__list">
              <li>감사 로그</li>
              <li>전용 지원</li>
            </ul>
          </div>
        </article>
      </div>
    </div>
    <div class="sw__dots">
      <button class="sw__dot" type="button" data-go="0" aria-current="true"><span class="sw__vh">스타터</span></button>
      <button class="sw__dot" type="button" data-go="1"><span class="sw__vh">프로</span></button>
      <button class="sw__dot" type="button" data-go="2"><span class="sw__vh">비즈니스</span></button>
    </div>
  </div>
</main>

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

$duration: $dur-base;
$easing: $ease-spring;
$color: $subject-sky;
$gapx: $sp-3; // 카드 사이 간격 — 무한 루프 트랙이 아니어도 flex gap 대신 margin-right 로 준다 (BD15)

@include stage($stage-ink);

.sw {
  box-sizing: border-box;
  width: min(300px, 82vw);
  display: flex;
  flex-direction: column;
  gap: $sp-3;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: $subject-cream;
}

// 뷰포트 상자와 트랙은 반드시 다른 요소다. transform 은 트랙에만 건다 —
// 뷰포트는 overflow: hidden 으로 잘라 내는 창이다. 창째 밀면 내용이 창과 함께 움직여 스크롤이 아예 일어나지 않는다
.sw__view {
  overflow: hidden;
  width: 100%;
  border-radius: $r-card;
  touch-action: pan-y;
  cursor: grab;
}

.sw__track {
  --i: 0;
  --dx: 0px;
  --base: calc(-1 * var(--i) * (100% + #{$gapx}));
  display: flex;
  transform: translateX(calc(var(--base) + var(--dx)));
  transition: transform $duration $easing;
}
.sw__track.is-drag { transition: none; }

.sw__card {
  box-sizing: border-box;
  flex: 0 0 auto;
  width: 100%;
  margin-right: $gapx;
}
.sw__card:last-child { margin-right: 0; }

.sw__inner {
  box-sizing: border-box;
  height: 100%;
  padding: $sp-4;
  border: 2px solid rgba(255, 255, 255, .14);
  border-radius: $r-card;
  background-color: rgba(255, 255, 255, .07);
}

.sw__name {
  display: flex;
  align-items: center;
  gap: $sp-2;
  margin: 0;
  font-size: 13px;
  line-height: 20px;
  font-weight: 700;
  color: $subject-cream;
}
.sw__nametext {
  min-width: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sw__tag {
  flex: 0 0 auto;
  padding-left: $sp-2;
  padding-right: $sp-2;
  border-radius: $r-pill;
  background-color: $color;
  color: $subject-ink;
  font-size: 10px;
  line-height: 18px;
  font-weight: 700;
}

.sw__price {
  display: flex;
  align-items: baseline;
  gap: $sp-1;
  margin-top: $sp-2;
  margin-bottom: $sp-2;
  margin-left: 0;
  margin-right: 0;
}
.sw__amt {
  font-size: 26px;
  line-height: 32px;
  font-weight: 800;
  color: $color;
}
.sw__per {
  font-size: 12px;
  line-height: 18px;
  font-weight: 500;
  color: rgba(255, 255, 255, .62);
}

.sw__list {
  margin: 0;
  padding: 0;
  list-style: none;
}
.sw__list li {
  position: relative;
  padding-left: $sp-4;
  font-size: 12px;
  line-height: 20px;
  font-weight: 500;
  color: $subject-cream;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sw__list li + li { margin-top: $sp-1; }
.sw__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: $color;
}

// ── 점 ──
.sw__dots {
  display: flex;
  justify-content: center;
  gap: $sp-2;
}
.sw__dot {
  position: relative;
  box-sizing: border-box;
  width: 8px;
  height: 8px;
  margin: 0;
  padding: 0;
  border: 0;
  border-radius: $r-pill;
  background-color: rgba(255, 255, 255, .28);
  cursor: pointer;
  transition: width $duration $easing, background-color $duration $easing;
}
.sw__dot[aria-current="true"] {
  width: 22px;
  background-color: $color;
}
.sw__dot:focus-visible { outline: 2px solid $color; outline-offset: 2px; }

.sw__vh {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  white-space: nowrap;
  clip-path: inset(50%);
}

// ── 자동 루프: 1→2→3 으로 밀고, 3→1 은 카드를 복제하지 않고 그대로 미끄러져 돌아온다 ──
.sw.is-demo .sw__track {
  animation-name: sw-slide;
  animation-duration: $dur-loop;
  animation-timing-function: $easing;
  animation-iteration-count: infinite;
}
@keyframes sw-slide {
  0%   { transform: translateX(0); }
  22%  { transform: translateX(0); }
  36%  { transform: translateX(calc(-1 * (100% + #{$gapx}))); }
  50%  { transform: translateX(calc(-1 * (100% + #{$gapx}))); }
  64%  { transform: translateX(calc(-2 * (100% + #{$gapx}))); }
  74%  { transform: translateX(calc(-2 * (100% + #{$gapx}))); }
  88%  { transform: translateX(0); }
  100% { transform: translateX(0); }
}

// 카드가 넘어갈 때마다 살짝 눌렸다 펴진다 — 컷만으로는 채워지지 않는 프레임을 메운다
.sw.is-demo .sw__inner {
  animation-name: sw-lift;
  animation-duration: $dur-loop;
  animation-timing-function: $easing;
  animation-iteration-count: infinite;
}
@keyframes sw-lift {
  0%   { transform: scale(1); }
  22%  { transform: scale(1); }
  30%  { transform: scale(.95); }
  43%  { transform: scale(1); }
  50%  { transform: scale(1); }
  58%  { transform: scale(.95); }
  70%  { transform: scale(1); }
  74%  { transform: scale(1); }
  81%  { transform: scale(.95); }
  90%  { transform: scale(1); }
  100% { transform: scale(1); }
}

// 점의 활성 표시는 컷 — 반투명하게 섞이면 유령 프레임이 남는다
.sw.is-demo .sw__dot {
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.sw.is-demo .sw__dot[data-go="0"] { animation-name: sw-dot-a; }
.sw.is-demo .sw__dot[data-go="1"] { animation-name: sw-dot-b; }
.sw.is-demo .sw__dot[data-go="2"] { animation-name: sw-dot-c; }

@keyframes sw-dot-a {
  0%   { width: 22px; background-color: $subject-sky; }
  36%  { width: 8px; background-color: rgba(255, 255, 255, .28); }
  88%  { width: 22px; background-color: $subject-sky; }
  100% { width: 22px; background-color: $subject-sky; }
}
@keyframes sw-dot-b {
  0%   { width: 8px; background-color: rgba(255, 255, 255, .28); }
  36%  { width: 22px; background-color: $subject-sky; }
  64%  { width: 8px; background-color: rgba(255, 255, 255, .28); }
  100% { width: 8px; background-color: rgba(255, 255, 255, .28); }
}
@keyframes sw-dot-c {
  0%   { width: 8px; background-color: rgba(255, 255, 255, .28); }
  64%  { width: 22px; background-color: $subject-sky; }
  88%  { width: 8px; background-color: rgba(255, 255, 255, .28); }
  100% { width: 8px; background-color: rgba(255, 255, 255, .28); }
}

@media (max-width: 340px) {
  .sw { gap: $sp-2; }
  .sw__inner { padding: $sp-2; }
  .sw__name { gap: $sp-1; font-size: 12px; line-height: 18px; }
  .sw__tag { font-size: 9px; line-height: 16px; }
  .sw__price { margin-top: $sp-1; margin-bottom: $sp-1; }
  .sw__amt { font-size: 22px; line-height: 26px; }
  .sw__per { font-size: 11px; line-height: 16px; }
  .sw__list li { padding-left: $sp-3; font-size: 11px; line-height: 16px; }
  .sw__list li::before { top: 5px; }
}

@media (prefers-reduced-motion: reduce) {
  .sw.is-demo .sw__track,
  .sw.is-demo .sw__inner,
  .sw.is-demo .sw__dot { animation: none !important; }
  .sw__track,
  .sw__dot { transition: none; }
}

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);
}

.sw {
  box-sizing: border-box;
  width: min(300px, 82vw);
  display: flex;
  flex-direction: column;
  gap: 12px;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: #fff7e6;
}

.sw__view {
  overflow: hidden;
  width: 100%;
  border-radius: 16px;
  touch-action: pan-y;
  cursor: grab;
}

.sw__track {
  --i: 0;
  --dx: 0px;
  --base: calc(-1 * var(--i) * (100% + 12px));
  display: flex;
  transform: translateX(calc(var(--base) + var(--dx)));
  transition: transform 300ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.sw__track.is-drag {
  transition: none;
}

.sw__card {
  box-sizing: border-box;
  flex: 0 0 auto;
  width: 100%;
  margin-right: 12px;
}

.sw__card:last-child {
  margin-right: 0;
}

.sw__inner {
  box-sizing: border-box;
  height: 100%;
  padding: 16px;
  border: 2px solid rgba(255, 255, 255, 0.14);
  border-radius: 16px;
  background-color: rgba(255, 255, 255, 0.07);
}

.sw__name {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0;
  font-size: 13px;
  line-height: 20px;
  font-weight: 700;
  color: #fff7e6;
}

.sw__nametext {
  min-width: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sw__tag {
  flex: 0 0 auto;
  padding-left: 8px;
  padding-right: 8px;
  border-radius: 999px;
  background-color: #6ec8ff;
  color: #17141a;
  font-size: 10px;
  line-height: 18px;
  font-weight: 700;
}

.sw__price {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-top: 8px;
  margin-bottom: 8px;
  margin-left: 0;
  margin-right: 0;
}

.sw__amt {
  font-size: 26px;
  line-height: 32px;
  font-weight: 800;
  color: #6ec8ff;
}

.sw__per {
  font-size: 12px;
  line-height: 18px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.62);
}

.sw__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.sw__list li {
  position: relative;
  padding-left: 16px;
  font-size: 12px;
  line-height: 20px;
  font-weight: 500;
  color: #fff7e6;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sw__list li + li {
  margin-top: 4px;
}

.sw__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: #6ec8ff;
}

.sw__dots {
  display: flex;
  justify-content: center;
  gap: 8px;
}

.sw__dot {
  position: relative;
  box-sizing: border-box;
  width: 8px;
  height: 8px;
  margin: 0;
  padding: 0;
  border: 0;
  border-radius: 999px;
  background-color: rgba(255, 255, 255, 0.28);
  cursor: pointer;
  transition: width 300ms cubic-bezier(0.2, 0.8, 0.2, 1), background-color 300ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.sw__dot[aria-current=true] {
  width: 22px;
  background-color: #6ec8ff;
}

.sw__dot:focus-visible {
  outline: 2px solid #6ec8ff;
  outline-offset: 2px;
}

.sw__vh {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  white-space: nowrap;
  clip-path: inset(50%);
}

.sw.is-demo .sw__track {
  animation-name: sw-slide;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 0.8, 0.2, 1);
  animation-iteration-count: infinite;
}

@keyframes sw-slide {
  0% {
    transform: translateX(0);
  }
  22% {
    transform: translateX(0);
  }
  36% {
    transform: translateX(calc(-1 * (100% + 12px)));
  }
  50% {
    transform: translateX(calc(-1 * (100% + 12px)));
  }
  64% {
    transform: translateX(calc(-2 * (100% + 12px)));
  }
  74% {
    transform: translateX(calc(-2 * (100% + 12px)));
  }
  88% {
    transform: translateX(0);
  }
  100% {
    transform: translateX(0);
  }
}
.sw.is-demo .sw__inner {
  animation-name: sw-lift;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 0.8, 0.2, 1);
  animation-iteration-count: infinite;
}

@keyframes sw-lift {
  0% {
    transform: scale(1);
  }
  22% {
    transform: scale(1);
  }
  30% {
    transform: scale(0.95);
  }
  43% {
    transform: scale(1);
  }
  50% {
    transform: scale(1);
  }
  58% {
    transform: scale(0.95);
  }
  70% {
    transform: scale(1);
  }
  74% {
    transform: scale(1);
  }
  81% {
    transform: scale(0.95);
  }
  90% {
    transform: scale(1);
  }
  100% {
    transform: scale(1);
  }
}
.sw.is-demo .sw__dot {
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.sw.is-demo .sw__dot[data-go="0"] {
  animation-name: sw-dot-a;
}

.sw.is-demo .sw__dot[data-go="1"] {
  animation-name: sw-dot-b;
}

.sw.is-demo .sw__dot[data-go="2"] {
  animation-name: sw-dot-c;
}

@keyframes sw-dot-a {
  0% {
    width: 22px;
    background-color: #6ec8ff;
  }
  36% {
    width: 8px;
    background-color: rgba(255, 255, 255, 0.28);
  }
  88% {
    width: 22px;
    background-color: #6ec8ff;
  }
  100% {
    width: 22px;
    background-color: #6ec8ff;
  }
}
@keyframes sw-dot-b {
  0% {
    width: 8px;
    background-color: rgba(255, 255, 255, 0.28);
  }
  36% {
    width: 22px;
    background-color: #6ec8ff;
  }
  64% {
    width: 8px;
    background-color: rgba(255, 255, 255, 0.28);
  }
  100% {
    width: 8px;
    background-color: rgba(255, 255, 255, 0.28);
  }
}
@keyframes sw-dot-c {
  0% {
    width: 8px;
    background-color: rgba(255, 255, 255, 0.28);
  }
  64% {
    width: 22px;
    background-color: #6ec8ff;
  }
  88% {
    width: 8px;
    background-color: rgba(255, 255, 255, 0.28);
  }
  100% {
    width: 8px;
    background-color: rgba(255, 255, 255, 0.28);
  }
}
@media (max-width: 340px) {
  .sw {
    gap: 8px;
  }
  .sw__inner {
    padding: 8px;
  }
  .sw__name {
    gap: 4px;
    font-size: 12px;
    line-height: 18px;
  }
  .sw__tag {
    font-size: 9px;
    line-height: 16px;
  }
  .sw__price {
    margin-top: 4px;
    margin-bottom: 4px;
  }
  .sw__amt {
    font-size: 22px;
    line-height: 26px;
  }
  .sw__per {
    font-size: 11px;
    line-height: 16px;
  }
  .sw__list li {
    padding-left: 12px;
    font-size: 11px;
    line-height: 16px;
  }
  .sw__list li::before {
    top: 5px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .sw.is-demo .sw__track,
  .sw.is-demo .sw__inner,
  .sw.is-demo .sw__dot {
    animation: none !important;
  }
  .sw__track,
  .sw__dot {
    transition: none;
  }
}

// 실제 동작: 카드는 3장뿐이다. 복제도 텔레포트도 없고 양 끝에서 그냥 멈춘다.
// transform 은 언제나 트랙에만 건다 — 잘라 내는 창인 뷰포트를 밀면 내용이 창과 함께 움직여 스크롤이 안 된다.
var root = document.querySelector('.sw');
var view = document.getElementById('sw-view');
var track = document.getElementById('sw-track');
var dots = [].slice.call(document.querySelectorAll('.sw__dot'));
var last = dots.length - 1;
var index = 0, startX = 0, dragging = false;

function step() { return view.getBoundingClientRect().width + 12; }
function go(k) {
  index = Math.max(0, Math.min(last, k)); // 끝을 넘지 않게 clamp
  track.style.setProperty('--i', String(index));
  track.style.setProperty('--dx', '0px');
  dots.forEach(function (d, j) {
    if (j === index) { d.setAttribute('aria-current', 'true'); } else { d.removeAttribute('aria-current'); }
  });
}
view.addEventListener('pointerdown', function (e) {
  root.classList.remove('is-demo');
  // 손가락이 상자 밖으로 나가도 move·up 이 계속 이 요소로 온다
  e.currentTarget.setPointerCapture(e.pointerId);
  dragging = true;
  startX = e.clientX;
  track.classList.add('is-drag');
});
view.addEventListener('pointermove', function (e) {
  if (!dragging) { return; }
  track.style.setProperty('--dx', (e.clientX - startX) + 'px');
});
function release(e) {
  if (!dragging) { return; }
  dragging = false;
  track.classList.remove('is-drag');
  go(index - Math.round((e.clientX - startX) / step())); // 가장 가까운 카드로 스냅
}
view.addEventListener('pointerup', release);
view.addEventListener('pointercancel', release);
dots.forEach(function (d, j) {
  d.addEventListener('click', function () { root.classList.remove('is-demo'); go(j); });
});
go(0);

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

export type SwipePlan = { name: string; price: string; tag?: string; features: [string, string] };
export type SwipePlanCardsProps = {
  plans?: SwipePlan[];
  per?: string;
  label?: string;
  duration?: number;
  easing?: string;
  color?: string;
};

// React 이벤트 타입은 'react' 앰비언트에 없다 — 쓰는 모양만 여기서 직접 적는다
type PtrEvt = {
  clientX: number;
  pointerId: number;
  currentTarget: { setPointerCapture(id: number): void; getBoundingClientRect(): { width: number } };
};
type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };
type TrackVars = CSSProperties & { "--i"?: string; "--dx"?: string };

const GAP = 12; // 카드 사이 간격 — scss 의 margin-right 와 같은 값

const DEFAULT_PLANS: SwipePlan[] = [
  { name: "Starter", price: "$9", features: ["Unlimited projects included", "Invite teammates"] },
  { name: "Pro", price: "$29", tag: "Popular", features: ["Priority support", "Invite teammates"] },
  { name: "Business", price: "$79", features: ["Audit log", "Dedicated support"] },
];

export default function SwipePlanCards({
  plans = DEFAULT_PLANS,
  per = "/ mo",
  label = "Swipe between plans",
  duration = 300,
  easing = "cubic-bezier(.2, .8, .2, 1)",
  color = "#6ec8ff",
}: SwipePlanCardsProps) {
  const [demo, setDemo] = useState(true);
  const [index, setIndex] = useState(0);
  const [dx, setDx] = useState(0);
  const [drag, setDrag] = useState(false);
  const [grab, setGrab] = useState({ x: 0, w: 0 }); // 잡은 지점과 그때의 뷰포트 너비
  const last = plans.length - 1;

  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };
  const trackVars: TrackVars = { "--i": String(index), "--dx": `${dx}px` };

  // 카드는 plans.length 장뿐이다. 복제도 텔레포트도 없고 양 끝에서 clamp 으로 멈춘다
  function go(k: number) {
    setIndex(Math.max(0, Math.min(last, k)));
    setDx(0);
  }
  function down(e: PtrEvt) {
    setDemo(false);
    // 손가락이 상자 밖으로 나가도 move·up 이 계속 이 요소로 온다
    e.currentTarget.setPointerCapture(e.pointerId);
    setGrab({ x: e.clientX, w: e.currentTarget.getBoundingClientRect().width });
    setDrag(true);
  }
  function move(e: PtrEvt) {
    if (!drag) return;
    setDx(e.clientX - grab.x);
  }
  function release(e: PtrEvt) {
    if (!drag) return;
    setDrag(false);
    go(index - Math.round((e.clientX - grab.x) / (grab.w + GAP))); // 가장 가까운 카드로 스냅
  }

  return (
    <div className={`${styles.sw} ${demo ? styles.isDemo : ""}`} style={vars} role="group" aria-label={label}>
      {/* 뷰포트 상자와 트랙은 다른 요소다. transform 은 트랙에만 — 잘라 내는 창인 뷰포트를 밀면 내용이 창과 함께 움직인다 */}
      <div
        className={styles.view}
        onPointerDown={down}
        onPointerMove={move}
        onPointerUp={release}
        onPointerCancel={release}
      >
        <div className={`${styles.track} ${drag ? styles.isDrag : ""}`} style={trackVars}>
          {plans.map((p) => (
            <article key={p.name} className={styles.card}>
              <div className={styles.inner}>
                <p className={styles.name}>
                  <span className={styles.nametext}>{p.name}</span>
                  {p.tag ? <span className={styles.tag}>{p.tag}</span> : null}
                </p>
                <p className={styles.price}>
                  <span className={styles.amt}>{p.price}</span>
                  <span className={styles.per}>{per}</span>
                </p>
                <ul className={styles.list}>
                  <li>{p.features[0]}</li>
                  <li>{p.features[1]}</li>
                </ul>
              </div>
            </article>
          ))}
        </div>
      </div>
      <div className={styles.dots}>
        {plans.map((p, i) => (
          <button
            key={p.name}
            className={styles.dot}
            type="button"
            data-go={String(i)}
            aria-current={i === index ? "true" : undefined}
            onClick={() => { setDemo(false); go(i); }}
          >
            <span className={styles.vh}>{p.name}</span>
          </button>
        ))}
      </div>
    </div>
  );
}