07Day/night icon toggle

<main class="stage">
  <label class="switch is-demo">
    <input type="checkbox" class="switch__input" role="switch">
    <span class="switch__track">
      <span class="switch__star switch__star--1"></span>
      <span class="switch__star switch__star--2"></span>
      <span class="switch__star switch__star--3"></span>
      <span class="switch__knob">
        <svg class="switch__icon switch__icon--sun" viewBox="0 0 16 16" width="11" height="11" aria-hidden="true">
          <circle cx="8" cy="8" r="3.2" fill="currentColor"/>
          <g stroke="currentColor" stroke-width="1.4" stroke-linecap="round">
            <line x1="8" y1="0.5" x2="8" y2="2.4"/>
            <line x1="8" y1="13.6" x2="8" y2="15.5"/>
            <line x1="0.5" y1="8" x2="2.4" y2="8"/>
            <line x1="13.6" y1="8" x2="15.5" y2="8"/>
          </g>
        </svg>
        <svg class="switch__icon switch__icon--moon" viewBox="0 0 16 16" width="11" height="11" aria-hidden="true">
          <path d="M10.5 2.5a6 6 0 100 11 7 7 0 010-11z" fill="currentColor"/>
        </svg>
      </span>
    </span>
    <span class="switch__label">Night mode</span>
  </label>
</main>

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

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

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

.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(56px, 15vw, 66px); height: clamp(28px, 7.5vw, 32px);
  border-radius: $r-pill;
  background-image: linear-gradient(90deg, $stage-yellow 0%, $stage-yellow 50%, $color 50%, $color 100%);
  background-size: 200% 100%;
  background-position: 0% 0%;
  transition: background-position $duration $easing;
}
.switch__star {
  position: absolute; top: 30%; width: 2.5px; height: 2.5px; border-radius: 50%;
  background: $subject-cream; opacity: 0;
  transition: opacity $duration $easing;
}
.switch__star--1 { left: 62%; top: 26%; }
.switch__star--2 { left: 74%; top: 55%; }
.switch__star--3 { left: 84%; top: 34%; }
.switch__knob {
  position: absolute; top: 3px; left: 3px; z-index: 1;
  display: grid; place-items: center;
  width: clamp(22px, 6vw, 26px); height: clamp(22px, 6vw, 26px);
  border-radius: 50%;
  background: $stage-paper;
  box-shadow: $shadow-raised;
  color: $stage-orange;
  transform: translateX(0);
  transition: transform $duration cubic-bezier(0.34, 1.56, 0.64, 1), color $duration $easing, box-shadow $duration $easing;
}
.switch__icon { grid-area: 1 / 1; transition: opacity $duration $easing; }
.switch__icon--sun  { opacity: 1; }
.switch__icon--moon { opacity: 0; }
.switch__label { color: $subject-ink; font-weight: 600; font-size: clamp(14px, 4vw, 17px); line-height: 1; font-family: inherit; }

// ── 실제 동작: 트랙 자체가 하늘, 노브 안 아이콘이 크로스페이드 ──────
.switch__input:checked ~ .switch__track { background-position: 100% 0%; }
.switch__input:checked ~ .switch__track .switch__star { opacity: 1; }
.switch__input:checked ~ .switch__track .switch__knob {
  transform: translateX(clamp(28px, 8vw, 34px));
  color: $subject-ink;
  box-shadow: 0 20px 32px rgba(23, 20, 26, .4);
}
.switch__input:checked ~ .switch__track .switch__icon--sun  { opacity: 0; }
.switch__input:checked ~ .switch__track .switch__icon--moon { opacity: 1; }

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

// ── 데모 루프 ─────────────────────────────
// 한 겹: 노브는 도착 지점을 지나쳤다 찌그러지며 안착하고(스프링+squash),
//        밤으로 갈 때 노브 그림자가 깊어진다(blur 증가·offset 하강 — 더 붙는 느낌).
.switch.is-demo .switch__track       { animation: sky-loop $dur-loop $easing infinite; }
.switch.is-demo .switch__star--1,
.switch.is-demo .switch__star--2,
.switch.is-demo .switch__star--3     { animation: star-loop $dur-loop $easing infinite; }
.switch.is-demo .switch__knob        { animation: knob-spring-loop $dur-loop $easing infinite, knob-shadow-loop $dur-loop $easing infinite; }
.switch.is-demo .switch__icon--sun   { animation: sun-loop $dur-loop $easing infinite; }
.switch.is-demo .switch__icon--moon  { animation: moon-loop $dur-loop $easing infinite; }

@keyframes sky-loop  { 0%, 15% { background-position: 0% 0%; } 40%, 60% { background-position: 100% 0%; } 85%, 100% { background-position: 0% 0%; } }
@keyframes star-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(34px); }
  85%, 100% { transform: translateX(0); }
}
@keyframes knob-spring-loop {
  0%, 15%   { transform: translateX(0) scaleX(1) scaleY(1); }
  38%       { transform: translateX(37px) scaleX(1.25) scaleY(.85); }  // 오버슈트 + 도착 순간 squash
  43%       { transform: translateX(33px) scaleX(1.08) scaleY(.94); }  // 되튕기며 회복
  47%, 60%  { transform: translateX(34px) 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 knob-shadow-loop {
  0%, 15%   { box-shadow: $shadow-raised; }
  40%, 60%  { box-shadow: 0 20px 32px rgba(23, 20, 26, .4); }
  85%, 100% { box-shadow: $shadow-raised; }
}
@keyframes sun-loop  { 0%, 15% { opacity: 1; } 40%, 60% { opacity: 0; } 85%, 100% { opacity: 1; } }
@keyframes moon-loop { 0%, 15% { opacity: 0; } 40%, 60% { opacity: 1; } 85%, 100% { opacity: 0; } }

@media (prefers-reduced-motion: reduce) {
  .switch.is-demo .switch__track, .switch.is-demo .switch__star--1, .switch.is-demo .switch__star--2,
  .switch.is-demo .switch__star--3, .switch.is-demo .switch__knob, .switch.is-demo .switch__icon--sun,
  .switch.is-demo .switch__icon--moon { animation: none !important; }
  .switch__track, .switch__star, .switch__knob, .switch__icon { transition: none; }
}

html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ff4d1f;
  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(56px, 15vw, 66px);
  height: clamp(28px, 7.5vw, 32px);
  border-radius: 999px;
  background-image: linear-gradient(90deg, #ffd23f 0%, #ffd23f 50%, #17141a 50%, #17141a 100%);
  background-size: 200% 100%;
  background-position: 0% 0%;
  transition: background-position 600ms ease-out;
}

.switch__star {
  position: absolute;
  top: 30%;
  width: 2.5px;
  height: 2.5px;
  border-radius: 50%;
  background: #fff7e6;
  opacity: 0;
  transition: opacity 600ms ease-out;
}

.switch__star--1 {
  left: 62%;
  top: 26%;
}

.switch__star--2 {
  left: 74%;
  top: 55%;
}

.switch__star--3 {
  left: 84%;
  top: 34%;
}

.switch__knob {
  position: absolute;
  top: 3px;
  left: 3px;
  z-index: 1;
  display: grid;
  place-items: center;
  width: clamp(22px, 6vw, 26px);
  height: clamp(22px, 6vw, 26px);
  border-radius: 50%;
  background: #ffffff;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  color: #ff4d1f;
  transform: translateX(0);
  transition: transform 600ms cubic-bezier(0.34, 1.56, 0.64, 1), color 600ms ease-out, box-shadow 600ms ease-out;
}

.switch__icon {
  grid-area: 1/1;
  transition: opacity 600ms ease-out;
}

.switch__icon--sun {
  opacity: 1;
}

.switch__icon--moon {
  opacity: 0;
}

.switch__label {
  color: #17141a;
  font-weight: 600;
  font-size: clamp(14px, 4vw, 17px);
  line-height: 1;
  font-family: inherit;
}

.switch__input:checked ~ .switch__track {
  background-position: 100% 0%;
}

.switch__input:checked ~ .switch__track .switch__star {
  opacity: 1;
}

.switch__input:checked ~ .switch__track .switch__knob {
  transform: translateX(clamp(28px, 8vw, 34px));
  color: #17141a;
  box-shadow: 0 20px 32px rgba(23, 20, 26, 0.4);
}

.switch__input:checked ~ .switch__track .switch__icon--sun {
  opacity: 0;
}

.switch__input:checked ~ .switch__track .switch__icon--moon {
  opacity: 1;
}

.switch__input:focus-visible ~ .switch__track {
  outline: 2px solid #17141a;
  outline-offset: 3px;
}

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

.switch.is-demo .switch__star--1,
.switch.is-demo .switch__star--2,
.switch.is-demo .switch__star--3 {
  animation: star-loop 2s ease-out infinite;
}

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

.switch.is-demo .switch__icon--sun {
  animation: sun-loop 2s ease-out infinite;
}

.switch.is-demo .switch__icon--moon {
  animation: moon-loop 2s ease-out infinite;
}

@keyframes sky-loop {
  0%, 15% {
    background-position: 0% 0%;
  }
  40%, 60% {
    background-position: 100% 0%;
  }
  85%, 100% {
    background-position: 0% 0%;
  }
}
@keyframes star-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(34px);
  }
  85%, 100% {
    transform: translateX(0);
  }
}
@keyframes knob-spring-loop {
  0%, 15% {
    transform: translateX(0) scaleX(1) scaleY(1);
  }
  38% {
    transform: translateX(37px) scaleX(1.25) scaleY(0.85);
  }
  43% {
    transform: translateX(33px) scaleX(1.08) scaleY(0.94);
  }
  47%, 60% {
    transform: translateX(34px) scaleX(1) scaleY(1);
  }
  84% {
    transform: translateX(-2px) scaleX(0.92) scaleY(1.06);
  }
  85%, 100% {
    transform: translateX(0) scaleX(1) scaleY(1);
  }
}
@keyframes knob-shadow-loop {
  0%, 15% {
    box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  }
  40%, 60% {
    box-shadow: 0 20px 32px rgba(23, 20, 26, 0.4);
  }
  85%, 100% {
    box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  }
}
@keyframes sun-loop {
  0%, 15% {
    opacity: 1;
  }
  40%, 60% {
    opacity: 0;
  }
  85%, 100% {
    opacity: 1;
  }
}
@keyframes moon-loop {
  0%, 15% {
    opacity: 0;
  }
  40%, 60% {
    opacity: 1;
  }
  85%, 100% {
    opacity: 0;
  }
}
@media (prefers-reduced-motion: reduce) {
  .switch.is-demo .switch__track, .switch.is-demo .switch__star--1, .switch.is-demo .switch__star--2,
  .switch.is-demo .switch__star--3, .switch.is-demo .switch__knob, .switch.is-demo .switch__icon--sun,
  .switch.is-demo .switch__icon--moon {
    animation: none !important;
  }
  .switch__track, .switch__star, .switch__knob, .switch__icon {
    transition: none;
  }
}

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 "./DayNightToggle.module.scss";

export type DayNightToggleProps = {
  label?: string;
  duration?: number;
  easing?: string;
  /** 밤 트랙 색 */
  color?: string;
  defaultChecked?: boolean;
  onChange?: (checked: boolean) => void;
};

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

export default function DayNightToggle({
  label = "야간 모드",
  duration = 600,
  easing = "ease-out",
  color = "#17141a",
  defaultChecked = false,
  onChange,
}: DayNightToggleProps) {
  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__star} ${styles["switch__star--1"]}`} />
        <span className={`${styles.switch__star} ${styles["switch__star--2"]}`} />
        <span className={`${styles.switch__star} ${styles["switch__star--3"]}`} />
        <span className={styles.switch__knob}>
          <svg className={styles["switch__icon--sun"]} viewBox="0 0 16 16" width="11" height="11" aria-hidden="true">
            <circle cx="8" cy="8" r="3.2" fill="currentColor" />
            <g stroke="currentColor" strokeWidth={1.4} strokeLinecap="round">
              <line x1="8" y1="0.5" x2="8" y2="2.4" />
              <line x1="8" y1="13.6" x2="8" y2="15.5" />
              <line x1="0.5" y1="8" x2="2.4" y2="8" />
              <line x1="13.6" y1="8" x2="15.5" y2="8" />
            </g>
          </svg>
          <svg className={styles["switch__icon--moon"]} viewBox="0 0 16 16" width="11" height="11" aria-hidden="true">
            <path d="M10.5 2.5a6 6 0 100 11 7 7 0 010-11z" fill="currentColor" />
          </svg>
        </span>
      </span>
      <span className={styles.switch__label}>{label}</span>
    </label>
  );
}