/* ============================================================
   章節舞台（Chapter 01–04）
   設計定案：docs/plans/2026-09-02-cinematic-chapters-design.md
   - 2026-09-02 改版：捲動不驅動任何鏡頭（真機上 sticky＋跟手指走的位移在 iOS 會微卡）。
     每章是一般區塊，進入畫面時「播一次」：手機升起 → 熱點亮起 → 幾幀自動輪播 → 文案換出章句。
   - 文字與截圖都是 DOM；沒有 JS、或 prefers-reduced-motion 時，內容全部靜態可見。
   ============================================================ */

.chapter {
    position: relative;
    color: #F3EEF8;
}

.chapter__sticky {
    position: relative;
    overflow: hidden;
    contain: paint;
}

/* 尺寸一律用固定值（rem／vw），不用視窗高度：LINE、FB 這類內建瀏覽器的工具列會隨滑動縮放，
   視窗高度一變，用視窗單位算的東西就會跟著忽大忽小、整頁抖動。 */
.chapter__stage {
    position: relative;
    display: grid;
    grid-template-rows: auto auto;
    justify-items: center;
    padding: 2rem 24px 1.5rem;
    perspective: 1200px;
}

/* 背景光層：從電影的暖色餘光接回品牌色，只動 opacity */
.chapter__glow {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}

.chapter__glow::before,
.chapter__glow::after {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(60% 50% at 50% 62%, rgba(255, 160, 80, 0.30), transparent 70%);
    opacity: 0;
}

.chapter__glow::after {
    background:
        radial-gradient(55% 45% at 30% 30%, rgba(255, 106, 43, 0.22), transparent 70%),
        radial-gradient(50% 45% at 75% 70%, rgba(255, 45, 139, 0.16), transparent 70%);
    opacity: 1;
}

.chapter__copy {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 30rem;
    display: grid;
}

/* 章節標頭三件套：編號 ── 名稱 ＋ 英文小字（蒸餾自 Kage 的 sec-head） */
.chapter__kicker {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin-bottom: 0.9rem;
}

.chapter__num {
    font-size: 0.72rem;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: rgba(255, 106, 43, 0.95);
    font-weight: 700;
}

.chapter__rule {
    width: 2rem;
    height: 1px;
    background: rgba(255, 106, 43, 0.55);
}

.chapter__name {
    font-size: 0.82rem;
    letter-spacing: 0.14em;
    color: rgba(243, 238, 248, 0.88);
    font-weight: 700;
}

.chapter__alt {
    font-size: 0.62rem;
    letter-spacing: 0.26em;
    color: rgba(243, 238, 248, 0.35);
    font-weight: 600;
}

/* 主標逐行遮罩浮現 */
.chapter__title .mask {
    display: inline-block;
    overflow: hidden;
    vertical-align: bottom;
    padding-bottom: 0.08em;
    margin-bottom: -0.08em;
}

.chapter__title .mask > span {
    display: inline-block;
}

/* 章末：下一章連結 */
.chapter__next {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    margin-top: 0.9rem;
    font-size: 0.85rem;
    font-weight: 700;
    color: rgba(255, 106, 43, 0.95);
    text-decoration: none;
    justify-self: center;
}

.chapter__next .icon {
    font-size: 0.9em;
}

.chapter__title {
    font-family: "Noto Serif TC", serif;
    font-weight: 900;
    font-size: clamp(1.55rem, 6.2vw, 2.4rem);
    line-height: 1.35;
    letter-spacing: -0.01em;
    display: grid;
}

.chapter__line {
    grid-area: 1 / 1;
    display: block;
}

.chapter__sub {
    margin-top: 0.8rem;
    font-size: 0.95rem;
    line-height: 1.7;
    color: rgba(243, 238, 248, 0.72);
    max-width: 24rem;
    justify-self: center;
}

/* 手機載體：沿用 index.html 的 .iphone-* 外殼，尺寸由可用高度決定 */
.chapter {
    /* 手機寬度固定（rem／vw），播影片時不會變。
       必須是絕對長度，不能給 .iphone-mockup 100%：外殼的邊框、圓角、瀏海都是 --phone-w 的百分比推算，
       百分比在垂直方向會改拿高度算，上下邊框就會胖一倍。 */
    --ch-phone-w: min(80vw, 19.5rem);
}

.chapter__phone {
    position: relative;
    z-index: 1;
    width: var(--ch-phone-w);
    margin-top: 1.5rem;
}

.chapter__phone .iphone-mockup {
    --phone-w: var(--ch-phone-w);
    transform: none;
    transition: none;
}

/* 螢幕內容：預先算好的循環短片（截圖＋交叉淡化烘進影片，硬體解碼，不靠 DOM 動畫） */
.chapter__video {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top center;
    background: #150C24;
}

/* 每幀＝一張 App 截圖＋它自己的遮罩；後面的幀疊在前面的幀上（舊模式，保留樣式備用） */
.chapter__frame {
    position: absolute;
    inset: 0;
}

.chapter__screen {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top center;
}

/* 出章幀：把上半部壓暗，只讓下方那顆交棒按鈕浮出來 */
.chapter__frame--spot::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, rgba(21, 12, 36, 0.82) 0%, rgba(21, 12, 36, 0.82) 60%, rgba(21, 12, 36, 0) 72%);
}

/* 熱點：即將被「按下／穿越」的按鈕或卡片，只做外圈光暈。
   陰影固定、只動 opacity（iOS 上動陰影本身會掉幀）。 */
.chapter__hot {
    position: absolute;
    border-radius: 999px;
    pointer-events: none;
    box-shadow:
        0 0 0 2px rgba(255, 140, 80, 1),
        0 0 32px 6px rgba(255, 106, 43, 0.55);
}

/* Bella 那張卡：跟底圖同一張圖、同一個尺度，靜止時看不出差別；
   穿越時它自己放大、發光，蓋進整個螢幕，再交叉淡化成聊天畫面。 */
.chapter__lift {
    position: absolute;
    left: 6%;
    top: 14.5%;
    width: 41%;
    height: 32.5%;
    border-radius: 8% / 5%;
    background-image: url("/assets/img/ch01-collection-grid.webp");
    background-size: 243.9% auto;
    background-position: 10.2% 21.5%;
    will-change: transform, opacity;
}

.chapter__lift::after {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    box-shadow:
        0 0 0 2px rgba(255, 140, 80, 1),
        0 0 40px 6px rgba(255, 106, 43, 0.6);
    opacity: var(--ch-hot-glow, 0);
}

/* 遮罩：蓋掉額度／扣則等不該入鏡的字。位置與底色由 inline style 給，
   底色取自該截圖同位置的像素（不用背景模糊，iOS 上太重）。 */
.chapter__mask {
    position: absolute;
    left: 0;
    right: 0;
}

/* ---------- 靜態退化（無 JS／reduced motion）：所有幀疊著，看到最後一幀 ---------- */
.chapter__line--exit { opacity: 0; }
.chapter__lift,
.chapter__hot { opacity: 0; }

/* ---------- 動態版：chapters.js 掛上 .chapter-motion-ready 後生效。
   進場前：手機在下方、文案在下方；.is-live：播進場；.is-done：文案換成出章句。 ---------- */
@media (prefers-reduced-motion: no-preference) {
    .chapter-motion-ready .chapter__copy {
        opacity: 0;
        transform: translate3d(0, 14px, 0);
        transition: opacity 0.6s ease-out, transform 0.7s cubic-bezier(0.2, 0.8, 0.2, 1);
    }

    .chapter-motion-ready .chapter__phone {
        opacity: 0;
        transform: translate3d(0, 56px, 0) rotateY(8deg);
        transition: opacity 0.7s ease-out 0.15s, transform 0.9s cubic-bezier(0.2, 0.8, 0.2, 1) 0.15s;
    }

    .chapter-motion-ready .chapter.is-live .chapter__copy,
    .chapter-motion-ready .chapter.is-live .chapter__phone {
        opacity: 1;
        transform: none;
    }

    /* 文案換句：播完最後一幀後，進場句淡出、出章句淡入 */
    .chapter-motion-ready .chapter__line--enter,
    .chapter-motion-ready .chapter__sub {
        transition: opacity 0.5s ease-out;
    }

    .chapter-motion-ready .chapter__title .mask > span {
        transform: translate3d(0, 112%, 0);
        transition: transform 0.85s cubic-bezier(0.2, 0.8, 0.2, 1) 0.1s;
    }

    .chapter-motion-ready .chapter__title .mask:nth-of-type(2) > span {
        transition-delay: 0.22s;
    }

    .chapter-motion-ready .chapter.is-live .chapter__title .mask > span {
        transform: none;
    }

    .chapter-motion-ready .chapter__next {
        opacity: 0;
        transform: translate3d(0, 6px, 0);
        transition: opacity 0.5s ease-out 0.25s, transform 0.5s ease-out 0.25s;
    }

    .chapter-motion-ready .chapter.is-done .chapter__next {
        opacity: 1;
        transform: none;
    }

    .chapter-motion-ready .chapter__line--exit {
        opacity: 0;
        transform: translate3d(0, 10px, 0);
        transition: opacity 0.6s ease-out 0.3s, transform 0.6s ease-out 0.3s;
    }

    /* 換句只換主標；副標留著，不然它淡出後會留一塊空位。Epilogue 沒有出章句，不換 */
    .chapter-motion-ready .chapter.is-done:not(.chapter--epilogue) .chapter__line--enter {
        opacity: 0;
    }

    .chapter-motion-ready .chapter.is-done .chapter__line--exit {
        opacity: 1;
        transform: none;
    }

    /* 熱點：進場後亮一下再暗，時間跟 chapters.js 的 PLAY.firstDelay 對齊 */
    .chapter-motion-ready .chapter.is-live .chapter__hot,
    .chapter-motion-ready .chapter.is-live .chapter__lift::after {
        animation: ch-hot 1.3s ease-in-out 0.8s both;
    }

    .chapter-motion-ready .chapter.is-live .chapter__lift {
        animation: ch-lift 1.3s ease-in-out 0.8s both;
    }

    @keyframes ch-hot {
        0% { opacity: 0; }
        45% { opacity: 1; }
        100% { opacity: 0; }
    }

    @keyframes ch-lift {
        0% { opacity: 1; transform: scale(1); }
        45% { opacity: 1; transform: scale(1.06); }
        100% { opacity: 1; transform: scale(1.1); }
    }

    /* 第 2 幀起用「推」進場：整張不透明地從 --ch-slide-x／--ch-slide-y 的方向滑進來蓋掉前一幀，
       任何時刻都只看到一層。方向可在章節或單一幀的 inline style 上指定。 */
    .chapter-motion-ready .chapter__frame[data-frame="1"] { opacity: 1; }
    .chapter-motion-ready .chapter__frame:not([data-frame="1"]):not(.is-on) { visibility: hidden; }
    .chapter-motion-ready .chapter__frame[data-frame="2"] { --f: var(--ch-frame-2, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="3"] { --f: var(--ch-frame-3, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="4"] { --f: var(--ch-frame-4, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="5"] { --f: var(--ch-frame-5, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="6"] { --f: var(--ch-frame-6, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="7"] { --f: var(--ch-frame-7, 0); }
    /* 淡入幀（App 裡是「點開放大」那種畫面）：透明度直接跟進度走，不推入 */
    .chapter-motion-ready .chapter__frame.chapter__frame--fade:not([data-frame="1"]) {
        opacity: var(--f, 0);
    }

    .chapter-motion-ready .chapter__frame:not([data-frame="1"]):not(.chapter__frame--fade) {
        opacity: min(1, calc(var(--f, 0) * 40));
        transform: translate3d(
            calc((1 - var(--f, 0)) * var(--ch-slide-x, 0%)),
            calc((1 - var(--f, 0)) * var(--ch-slide-y, 100%)),
            0
        );
    }

    /* 像 App 的換頁：新頁減速滑入時，舊頁同時往同方向退四分之一並壓暗（--n 是下一幀的進度） */
    .chapter-motion-ready .chapter__frame[data-frame="1"] { --n: var(--ch-frame-2, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="2"] { --n: var(--ch-frame-3, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="3"] { --n: var(--ch-frame-4, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="4"] { --n: var(--ch-frame-5, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="5"] { --n: var(--ch-frame-6, 0); }
    .chapter-motion-ready .chapter__frame[data-frame="6"] { --n: var(--ch-frame-7, 0); }

    .chapter-motion-ready .chapter__frame.is-on:not(.chapter__frame--fade),
    .chapter-motion-ready .chapter__frame[data-frame="1"] {
        transform: translate3d(
            calc((1 - var(--f, 1)) * var(--ch-slide-x, 0%) - var(--n, 0) * var(--ch-slide-x, 0%) * 0.25),
            calc((1 - var(--f, 1)) * var(--ch-slide-y, 100%) - var(--n, 0) * var(--ch-slide-y, 100%) * 0.12),
            0
        );
    }

    .chapter-motion-ready .chapter__frame::after {
        content: "";
        position: absolute;
        inset: 0;
        background: #000;
        opacity: calc(var(--n, 0) * 0.35);
        pointer-events: none;
    }
}

/* 桌面：跟 Hero 一樣左文右機，手機放到跟 Hero 那支同級 */
@media (min-width: 768px) {
    .chapter__stage {
        width: min(72rem, 100%);
        margin-inline: auto;
        grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
        grid-template-rows: none;
        align-items: center;
        column-gap: clamp(2rem, 6vw, 6rem);
        padding: 3rem 24px 3rem;
        min-height: 40rem;
    }

    .chapter__copy {
        text-align: left;
        justify-self: start;
        max-width: 44rem;
    }

    .chapter__kicker {
        justify-content: flex-start;
    }

    .chapter__next {
        justify-self: start;
    }

    .chapter__title {
        font-size: clamp(2.2rem, 3.6vw, 3.4rem);
    }

    .chapter__sub {
        justify-self: start;
        font-size: 1.05rem;
        max-width: 30rem;
    }

    .chapter__phone {
        align-self: center;
        justify-self: center;
        margin-top: 0;
    }

    .chapter {
        --ch-phone-w: clamp(300px, 26vw, 400px);
    }
}

/* ============================================================
   載入畫面（真實圖片載入進度，最多 2.5 秒）
   ============================================================ */
.site-loader {
    position: fixed;
    inset: 0;
    z-index: 100;
    display: grid;
    place-items: center;
    background: #150C24;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.55s ease, visibility 0s linear 0.55s;
}

html.is-loading .site-loader {
    opacity: 1;
    visibility: visible;
    transition: none;
}

html.is-loading body {
    overflow: hidden;
}

.site-loader__in {
    text-align: center;
}

.site-loader__brand {
    font-weight: 900;
    font-size: 1.7rem;
    letter-spacing: -0.02em;
    color: #fff;
}

.site-loader__brand span {
    color: #FF6A2B;
}

.site-loader__line {
    margin-top: 0.5rem;
    font-size: 0.85rem;
    letter-spacing: 0.1em;
    color: rgba(243, 238, 248, 0.6);
}

.site-loader__bar {
    width: 10rem;
    height: 2px;
    margin: 1.3rem auto 0;
    border-radius: 2px;
    background: rgba(255, 255, 255, 0.12);
    overflow: hidden;
}

.site-loader__bar span {
    display: block;
    height: 100%;
    width: 0;
    background: linear-gradient(90deg, #FF6A2B, #FF2D8B);
    transition: width 0.25s ease;
}

.site-loader__pct {
    margin-top: 0.6rem;
    font-size: 0.7rem;
    letter-spacing: 0.22em;
    color: rgba(243, 238, 248, 0.4);
    font-variant-numeric: tabular-nums;
}

@media (max-width: 767px) {
    /* 手機版兩顆商店徽章並排：縮到一列放得下 */
    .film-portal__copy a[href*="apps.apple.com"] img,
    .store-badge--play img,
    .chapter__cta img,
    .chapter__cta.store-badge--play img {
        height: 2.9rem !important;
    }
}

/* ============================================================
   Epilogue
   ============================================================ */
.chapter__stage--epilogue {
    grid-template-columns: 1fr;
    justify-items: center;
    min-height: 0;
    padding-bottom: 3rem;
}

.chapter__stage--epilogue .chapter__copy {
    text-align: center;
    justify-self: center;
}

.chapter__stage--epilogue .chapter__kicker {
    justify-content: center;
}

.chapter__sub--long {
    max-width: 34rem;
    font-size: 0.9rem;
    color: rgba(243, 238, 248, 0.62);
    justify-self: center !important;
}

.chapter__cta-row {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 0.75rem;
    margin-top: 1.4rem;
}

.chapter__cta {
    display: inline-block;
}

.chapter__cta img {
    height: 3.4rem;
    width: auto;
}

/* Google Play 徽章已裁掉上下透明邊（646×192，比例與 App Store 徽章一致），兩顆同高即同大 */
.store-badge--play img {
    height: 3.5rem;
    width: auto;
}

.film-portal__copy a[href*="apps.apple.com"] img {
    height: 3.5rem;
    width: auto;
}

.chapter__cta img,
.chapter__cta.store-badge--play img {
    height: 3.4rem;
}

/* ============================================================
   桌面：手機跟著游標微傾（不跟捲動）
   ============================================================ */
@media (hover: hover) and (pointer: fine) {
    .iphone-stage {
        transform: perspective(1200px) rotateY(var(--tilt-y, 0deg)) rotateX(var(--tilt-x, 0deg));
        transition: transform 0.5s ease-out;
    }
}

/* Google Play 上架前：徽章不可點，壓淡並標「即將推出」 */
.store-badge--soon {
    position: relative;
    display: inline-block;
    opacity: 0.55;
    cursor: default;
}

.store-badge--soon em {
    position: absolute;
    left: 50%;
    bottom: -0.15rem;
    transform: translate(-50%, 100%);
    font-style: normal;
    font-size: 0.62rem;
    letter-spacing: 0.14em;
    white-space: nowrap;
    color: rgba(243, 238, 248, 0.6);
}

.chapter__sub--long a {
    color: rgba(255, 106, 43, 0.95);
    text-decoration: underline;
    text-underline-offset: 0.18em;
}

/* 尾聲：回頭看正式片（Epilogue 沒有出章句，這條一進場就顯示） */
.chapter__next--film {
    margin-top: 1.2rem;
    justify-self: center !important;
}

.chapter-motion-ready .chapter.is-live .chapter__next--film {
    opacity: 1;
    transform: none;
}