01Trượt cơ bản

<main class="stage">
  <label class="switch is-demo">
    <input type="checkbox" class="switch__input" role="switch">
    <span class="switch__track">
      <span class="switch__bg switch__bg--off"></span>
      <span class="switch__bg switch__bg--on"></span>
      <span class="switch__knob"></span>
    </span>
    <span class="switch__label">Thông báo</span>
  </label>
</main>

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

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

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

.switch {
  position: relative;
  display: inline-flex; align-items: center; gap: clamp(10px, 3vw, 14px);
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}
.switch__input {
  position: absolute; inset: 0; width: 100%; height: 100%;
  margin: 0; opacity: 0; cursor: pointer;
}
.switch__track {
  position: relative; overflow: hidden;
  width: clamp(44px, 12vw, 52px); height: clamp(24px, 6.5vw, 28px);
  border-radius: $r-pill;
}
.switch__bg { position: absolute; inset: 0; }
.switch__bg--off { background: rgba(255, 255, 255, .18); opacity: 1; }
.switch__bg--on  { background: $color; opacity: 0; }
.switch__knob {
  position: absolute; top: 3px; left: 3px; z-index: 1;
  width: clamp(18px, 5vw, 22px); height: clamp(18px, 5vw, 22px);
  border-radius: 50%;
  background: $subject-cream;
  box-shadow: $shadow-press;
  transform: translateX(0);
  transition: transform $duration cubic-bezier(0.34, 1.56, 0.64, 1);
}
.switch__label { color: $subject-cream; font-weight: 600; font-size: clamp(14px, 4vw, 17px); line-height: 1; font-family: inherit; }

// ── 실제 동작: :checked 로 진짜 토글된다 ──────────────────
.switch__input:checked ~ .switch__track .switch__bg--off { opacity: 0; transition: opacity $duration $easing; }
.switch__input:checked ~ .switch__track .switch__bg--on  { opacity: 1; transition: opacity $duration $easing; }
.switch__input:checked ~ .switch__track .switch__knob    { transform: translateX(clamp(20px, 6vw, 24px)); }

.switch__input:focus-visible ~ .switch__track {
  outline: 2px solid $subject-cream; outline-offset: 3px;
}

// ── 데모 루프: 클릭 전까지 스스로 켜졌다 꺼진다 ──────────────
// 한 겹: 노브는 도착 지점을 지나쳤다 되돌아오며 찌그러지고(스프링 오버슛+squash),
//        트랙은 상태가 바뀌는 순간 내부 그림자가 깊어졌다 얕아진다(바닥에 앉는 깊이).
.switch.is-demo .switch__bg--off { animation: bg-off-loop $dur-loop $easing infinite; }
.switch.is-demo .switch__bg--on  { animation: bg-on-loop $dur-loop $easing infinite; }
.switch.is-demo .switch__knob    { animation: knob-spring-loop $dur-loop $easing infinite; }
.switch.is-demo .switch__track   { animation: shadow-depth-loop $dur-loop $easing infinite; }

@keyframes bg-off-loop { 0%, 15% { opacity: 1; } 40%, 60% { opacity: 0; } 85%, 100% { opacity: 1; } }
@keyframes bg-on-loop  { 0%, 15% { opacity: 0; } 40%, 60% { opacity: 1; } 85%, 100% { opacity: 0; } }
@keyframes knob-loop {
  0%, 15%   { transform: translateX(0); }
  40%, 60%  { transform: translateX(24px); }
  85%, 100% { transform: translateX(0); }
}
@keyframes knob-spring-loop {
  0%, 15%   { transform: translateX(0) scaleX(1) scaleY(1); }
  38%       { transform: translateX(27px) scaleX(1.25) scaleY(.85); }   // 오버슈트 + 도착 순간 squash
  42%       { transform: translateX(23.5px) scaleX(1.08) scaleY(.94); } // 되튕기며 회복
  46%, 60%  { transform: translateX(24px) scaleX(1) scaleY(1); }        // 안착
  84%       { transform: translateX(-2px) scaleX(.92) scaleY(1.06); }   // 출발 반동
  85%, 100% { transform: translateX(0) scaleX(1) scaleY(1); }
}
@keyframes shadow-depth-loop {
  0%, 15%   { box-shadow: inset 0 1px 3px rgba(0, 0, 0, .15); }
  38%       { box-shadow: inset 0 3px 8px rgba(0, 0, 0, .28); }   // 노브가 내려앉는 순간 깊어짐
  40%, 60%  { box-shadow: inset 0 3px 8px rgba(0, 0, 0, .28); }
  85%, 100% { box-shadow: inset 0 1px 3px rgba(0, 0, 0, .15); }
}

// ── 접근성: 움직임 줄이기 설정이면 전환만 남기고 데모 루프는 끈다 ──────
@media (prefers-reduced-motion: reduce) {
  .switch.is-demo .switch__bg--off,
  .switch.is-demo .switch__bg--on,
  .switch.is-demo .switch__knob,
  .switch.is-demo .switch__track { animation: none !important; }
  .switch__knob, .switch__bg--off, .switch__bg--on { 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);
}

.switch {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: clamp(10px, 3vw, 14px);
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

.switch__input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  opacity: 0;
  cursor: pointer;
}

.switch__track {
  position: relative;
  overflow: hidden;
  width: clamp(44px, 12vw, 52px);
  height: clamp(24px, 6.5vw, 28px);
  border-radius: 999px;
}

.switch__bg {
  position: absolute;
  inset: 0;
}

.switch__bg--off {
  background: rgba(255, 255, 255, 0.18);
  opacity: 1;
}

.switch__bg--on {
  background: #2f6df6;
  opacity: 0;
}

.switch__knob {
  position: absolute;
  top: 3px;
  left: 3px;
  z-index: 1;
  width: clamp(18px, 5vw, 22px);
  height: clamp(18px, 5vw, 22px);
  border-radius: 50%;
  background: #fff7e6;
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
  transform: translateX(0);
  transition: transform 300ms cubic-bezier(0.34, 1.56, 0.64, 1);
}

.switch__label {
  color: #fff7e6;
  font-weight: 600;
  font-size: clamp(14px, 4vw, 17px);
  line-height: 1;
  font-family: inherit;
}

.switch__input:checked ~ .switch__track .switch__bg--off {
  opacity: 0;
  transition: opacity 300ms ease-out;
}

.switch__input:checked ~ .switch__track .switch__bg--on {
  opacity: 1;
  transition: opacity 300ms ease-out;
}

.switch__input:checked ~ .switch__track .switch__knob {
  transform: translateX(clamp(20px, 6vw, 24px));
}

.switch__input:focus-visible ~ .switch__track {
  outline: 2px solid #fff7e6;
  outline-offset: 3px;
}

.switch.is-demo .switch__bg--off {
  animation: bg-off-loop 2s ease-out infinite;
}

.switch.is-demo .switch__bg--on {
  animation: bg-on-loop 2s ease-out infinite;
}

.switch.is-demo .switch__knob {
  animation: knob-spring-loop 2s ease-out infinite;
}

.switch.is-demo .switch__track {
  animation: shadow-depth-loop 2s ease-out infinite;
}

@keyframes bg-off-loop {
  0%, 15% {
    opacity: 1;
  }
  40%, 60% {
    opacity: 0;
  }
  85%, 100% {
    opacity: 1;
  }
}
@keyframes bg-on-loop {
  0%, 15% {
    opacity: 0;
  }
  40%, 60% {
    opacity: 1;
  }
  85%, 100% {
    opacity: 0;
  }
}
@keyframes knob-loop {
  0%, 15% {
    transform: translateX(0);
  }
  40%, 60% {
    transform: translateX(24px);
  }
  85%, 100% {
    transform: translateX(0);
  }
}
@keyframes knob-spring-loop {
  0%, 15% {
    transform: translateX(0) scaleX(1) scaleY(1);
  }
  38% {
    transform: translateX(27px) scaleX(1.25) scaleY(0.85);
  }
  42% {
    transform: translateX(23.5px) scaleX(1.08) scaleY(0.94);
  }
  46%, 60% {
    transform: translateX(24px) scaleX(1) scaleY(1);
  }
  84% {
    transform: translateX(-2px) scaleX(0.92) scaleY(1.06);
  }
  85%, 100% {
    transform: translateX(0) scaleX(1) scaleY(1);
  }
}
@keyframes shadow-depth-loop {
  0%, 15% {
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.15);
  }
  38% {
    box-shadow: inset 0 3px 8px rgba(0, 0, 0, 0.28);
  }
  40%, 60% {
    box-shadow: inset 0 3px 8px rgba(0, 0, 0, 0.28);
  }
  85%, 100% {
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.15);
  }
}
@media (prefers-reduced-motion: reduce) {
  .switch.is-demo .switch__bg--off,
  .switch.is-demo .switch__bg--on,
  .switch.is-demo .switch__knob,
  .switch.is-demo .switch__track {
    animation: none !important;
  }
  .switch__knob, .switch__bg--off, .switch__bg--on {
    transition: none;
  }
}

// 실제 클릭이 오면 데모 루프(.is-demo)를 떼고 :checked 로만 움직이게 한다.
// aria-checked 는 role="switch" 를 쓴 네이티브 체크박스라 브라우저가 checked 에서 자동으로 읽지만,
// 오래된 스크린리더까지 챙기려면 change 때마다 명시적으로 맞춰 둔다.
document.querySelectorAll(".switch").forEach(function (s) {
  var input = s.querySelector(".switch__input");
  var sync = function () { input.setAttribute("aria-checked", String(input.checked)); };
  input.addEventListener("pointerdown", function () { s.classList.remove("is-demo"); });
  input.addEventListener("change", sync);
  sync();
});

import { useState } from "react";
import type { ChangeEvent, CSSProperties } from "react";
import styles from "./ToggleSwitch.module.scss";

export type ToggleSwitchProps = {
  label?: string;
  /** 전환 시간 (기본 300ms) */
  duration?: number;
  /** CSS easing (기본 스프링 오버슛) */
  easing?: string;
  /** on 상태 트랙 색 */
  color?: string;
  defaultChecked?: boolean;
  onChange?: (checked: boolean) => void;
};

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

export default function ToggleSwitch({
  label = "알림",
  duration = 300,
  easing = "cubic-bezier(0.34, 1.56, 0.64, 1)",
  color = "#2f6df6",
  defaultChecked = false,
  onChange,
}: ToggleSwitchProps) {
  const [checked, setChecked] = useState(defaultChecked);

  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <label className={styles.switch} style={vars}>
      <input
        type="checkbox"
        role="switch"
        aria-checked={checked}
        className={styles.switch__input}
        checked={checked}
        onChange={(e: ChangeEvent<HTMLInputElement>) => {
          setChecked(e.target.checked);
          onChange?.(e.target.checked);
        }}
      />
      <span className={styles.switch__track}>
        <span className={styles["switch__bg--off"]} />
        <span className={styles["switch__bg--on"]} />
        <span className={styles.switch__knob} />
      </span>
      <span className={styles.switch__label}>{label}</span>
    </label>
  );
}