/* =====================================================================
   Shared core — layout, loader, drawer, controls, showcase, detail.
   Each direction (A / B / C) layers its own theme file on top of this.
   ===================================================================== */

/* ---------- Tokens (directions override these) ---------- */
:root {
  --font-latin: "Times New Roman", Times, "Liberation Serif", "Tinos", serif;
  /* Self-hosted 思源宋体 / 思源黑体 (fonts/fonts.css); system fonts only as fallback — never SimSun or KaiTi */
  --font-zh-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei UI", "Microsoft YaHei", sans-serif;
  --font-zh-sans: "Noto Sans SC", "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei UI", "Microsoft YaHei", "Source Han Sans SC", "WenQuanYi Zen Hei", sans-serif;
  --font-tw-serif: "Noto Serif TC", "Source Han Serif TC", "Songti TC", "Noto Sans TC", "PingFang TC", "Microsoft JhengHei UI", "Microsoft JhengHei", sans-serif;
  --font-tw-sans: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei UI", "Microsoft JhengHei", "Source Han Sans TC", "WenQuanYi Zen Hei", sans-serif;
  --font-ui: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;

  --font-display: var(--font-latin), var(--font-zh-serif);
  --font-body: var(--font-latin), var(--font-zh-sans);

  --ease-out: cubic-bezier(.16, 1, .3, 1);
  --ease-in-out: cubic-bezier(.65, 0, .35, 1);
  --ease-spring: cubic-bezier(.34, 1.56, .64, 1);

  --gutter: clamp(16px, 4vw, 56px);
  --radius: 18px;
  --radius-sm: 10px;
  --drawer-w: min(380px, 86vw);
  --topbar-h: 72px;

  /* light defaults */
  --bg: #eef1f0;
  --fg: #16201f;
  --fg-dim: rgba(22, 32, 31, .62);
  --fg-faint: rgba(22, 32, 31, .14);
  --line: rgba(22, 32, 31, .12);
  --accent: #b5703a;
  --accent-ink: #fff;
  --glass: rgba(255, 255, 255, .42);
  --glass-strong: rgba(255, 255, 255, .66);
  --glass-brd: rgba(255, 255, 255, .7);
  --glass-hi: rgba(255, 255, 255, .9);
  --shadow: 0 24px 60px -24px rgba(20, 30, 30, .35);
  --scrim: rgba(10, 16, 16, .28);
  --blur: 22px;
  color-scheme: light;
}
:root[data-theme="dark"] {
  --bg: #0b1113;
  --fg: #dde4e3;
  --fg-dim: rgba(221, 228, 227, .62);
  --fg-faint: rgba(221, 228, 227, .14);
  --line: rgba(221, 228, 227, .12);
  --accent: #e8a468;
  --accent-ink: #0b1113;
  --glass: rgba(16, 24, 27, .38);
  --glass-strong: rgba(16, 24, 27, .7);
  --glass-brd: rgba(255, 255, 255, .1);
  --glass-hi: rgba(255, 255, 255, .18);
  --shadow: 0 30px 70px -30px rgba(0, 0, 0, .8);
  --scrim: rgba(0, 0, 0, .45);
  color-scheme: dark;
}

/* Language-aware font stacks */
:root:lang(zh-TW) {
  --font-display: var(--font-latin), var(--font-tw-serif);
  --font-body: var(--font-latin), var(--font-tw-sans);
}
:root:lang(zh-CN) body, :root:lang(zh-TW) body { letter-spacing: .02em; }

/* ---------- Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 24px; }
body {
  margin: 0; min-height: 100vh; min-height: 100dvh;
  background: var(--bg); color: var(--fg);
  font-family: var(--font-body); font-size: 17px; line-height: 1.7;
  -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility;
  font-synthesis: none; font-kerning: normal; font-feature-settings: "palt" 0;
  overflow-x: hidden;
  transition: background-color .8s var(--ease-in-out), color .8s var(--ease-in-out);
}
body.is-locked { overflow: hidden; }
img, svg, canvas { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; -webkit-tap-highlight-color: transparent; }
a { color: inherit; text-decoration: none; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }
::selection { background: var(--accent); color: var(--accent-ink); }
.sr-only { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
em, .it { font-style: italic; }
/* CJK has no true italics — emphasise Chinese with colour only, keep Latin italic */
:root:lang(zh-CN) em:not([lang="en"]), :root:lang(zh-TW) em:not([lang="en"]) { font-style: normal; }

/* ---------- Background canvas ---------- */
#bg { position: fixed; inset: 0; width: 100%; height: 100%; z-index: 0; pointer-events: none; }
.grain {
  position: fixed; inset: 0; z-index: 1; pointer-events: none; opacity: .06;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 .5  0 0 0 0 .5  0 0 0 0 .5  0 0 0 1 0'/></filter><rect width='100%' height='100%' filter='url(%23n)'/></svg>");
  animation: grain 1.2s steps(6) infinite;
}
:root[data-theme="dark"] .grain { opacity: .09; }
@keyframes grain {
  0% { background-position: 0 0; } 20% { background-position: -37px 23px; } 40% { background-position: 29px -51px; }
  60% { background-position: -61px -13px; } 80% { background-position: 41px 37px; } 100% { background-position: 0 0; }
}

/* ---------- Glass primitive ---------- */
.glass {
  background: var(--glass);
  -webkit-backdrop-filter: blur(var(--blur)) saturate(150%);
  backdrop-filter: blur(var(--blur)) saturate(150%);
  border: 1px solid var(--glass-brd);
  box-shadow: inset 0 1px 0 var(--glass-hi), var(--shadow);
}

/* =====================================================================
   LOADER — greetings appear one after another
   ===================================================================== */
#loader {
  position: fixed; inset: 0; z-index: 100;
  display: grid; place-items: center;
  background: var(--loader-bg, #0c1215); color: var(--loader-fg, #e7ecea);
  clip-path: inset(0 0 0 0);
  transition: clip-path 1.1s var(--ease-in-out), opacity .6s ease 0.6s;
}
#loader.is-out { clip-path: inset(0 0 100% 0); pointer-events: none; }
#loader.is-gone { display: none; }
.loader__stage { position: relative; height: 1.4em; font-size: clamp(40px, 8vw, 92px); line-height: 1.4; min-width: 6ch; text-align: center; }
.loader__word {
  position: absolute; left: 50%; top: 0; white-space: nowrap;
  font-family: var(--font-display); font-style: italic; font-weight: 400;
  transform: translate(-50%, 40%); opacity: 0; filter: blur(12px);
  transition: transform .7s var(--ease-out), opacity .5s ease, filter .7s var(--ease-out);
}
.loader__word[lang^="zh"], .loader__word[lang="ja"], .loader__word[lang="ko"] { font-style: normal; font-weight: 400; letter-spacing: .06em; }
.loader__word[lang="zh-CN"] { font-family: var(--font-latin), var(--font-zh-serif); }
.loader__word[lang="zh-TW"] { font-family: var(--font-latin), var(--font-tw-serif); }
.loader__word[lang="ja"] { font-family: "Noto Serif JP", "Yu Mincho", "Hiragino Mincho ProN", var(--font-zh-serif), serif; }
.loader__word[lang="ko"] { font-family: "Noto Serif KR", "Nanum Myeongjo", "Malgun Gothic", "Apple SD Gothic Neo", serif; }
.loader__word.is-in { transform: translate(-50%, 0); opacity: 1; filter: blur(0); }
.loader__word.is-past { transform: translate(-50%, -40%); opacity: 0; filter: blur(10px); }
.loader__word::before {
  content: ""; position: absolute; left: -.55em; top: 50%; width: .16em; height: .16em; border-radius: 50%;
  background: var(--loader-accent, #e8a468); transform: translateY(-50%);
}
.loader__meta {
  position: absolute; left: 0; right: 0; bottom: max(32px, env(safe-area-inset-bottom));
  display: flex; justify-content: space-between; align-items: center; padding: 0 var(--gutter);
  font: 12px/1 var(--font-ui); letter-spacing: .18em; text-transform: uppercase; opacity: .55;
}
.loader__bar { position: absolute; left: 0; bottom: 0; height: 2px; width: 100%; background: currentColor; opacity: .12; }
.loader__bar span { display: block; height: 100%; width: 0; background: var(--loader-accent, #e8a468); transition: width .5s var(--ease-out); }
.loader__skip { padding: 10px 14px; margin: -10px -14px; letter-spacing: inherit; text-transform: inherit; opacity: 1; }
.loader__skip:hover { opacity: .9; text-decoration: underline; text-underline-offset: 4px; }

/* Content entrance after loader */
[data-enter] { opacity: 0; transform: translateY(24px); filter: blur(6px); }
body.is-ready [data-enter] {
  opacity: 1; transform: none; filter: none;
  transition: opacity 1.1s var(--ease-out), transform 1.2s var(--ease-out), filter 1.1s var(--ease-out);
  transition-delay: calc(var(--d, 0) * 110ms + 250ms);
}

/* =====================================================================
   TOP BAR — one menu button + quick theme/lang
   ===================================================================== */
.topbar {
  position: fixed; z-index: 40; top: 0; left: 0; right: 0; height: var(--topbar-h);
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 0 var(--gutter); pointer-events: none;
}
.topbar > * { pointer-events: auto; }
.topbar::before {
  content: ""; position: absolute; inset: 0 0 -28px; z-index: -1; pointer-events: none; opacity: 0;
  background: linear-gradient(var(--bg) 35%, color-mix(in srgb, var(--bg) 0%, transparent));
  transition: opacity .5s var(--ease-out);
}
.topbar.is-scrolled::before { opacity: .92; }
.menu-btn {
  display: inline-flex; align-items: center; gap: 12px; height: 46px; padding: 0 18px 0 8px; border-radius: 999px;
  font: 13px/1 var(--font-ui); letter-spacing: .14em; text-transform: uppercase;
  transition: transform .4s var(--ease-out), background-color .3s;
}
.menu-btn:hover { transform: translateY(-1px); }
.menu-btn__icon { position: relative; width: 30px; height: 30px; border-radius: 50%; background: var(--fg); }
.menu-btn__icon span {
  position: absolute; left: 9px; width: 12px; height: 1.5px; border-radius: 2px; background: var(--bg);
  transition: transform .45s var(--ease-out), width .45s var(--ease-out);
}
.menu-btn__icon span:nth-child(1) { top: 11px; }
.menu-btn__icon span:nth-child(2) { top: 17px; width: 8px; }
.menu-btn:hover .menu-btn__icon span:nth-child(2) { width: 12px; }
.menu-btn[aria-expanded="true"] .menu-btn__icon span:nth-child(1) { transform: translateY(3px) rotate(45deg); }
.menu-btn[aria-expanded="true"] .menu-btn__icon span:nth-child(2) { width: 12px; transform: translateY(-3px) rotate(-45deg); }
.topbar__right { display: flex; align-items: center; gap: 8px; }

.icon-btn {
  width: 46px; height: 46px; border-radius: 50%; display: grid; place-items: center;
  transition: transform .4s var(--ease-out);
}
.icon-btn:hover { transform: rotate(-12deg) scale(1.04); }
.icon-btn svg { width: 20px; height: 20px; }
.theme-icon .sun { transition: transform .6s var(--ease-out), opacity .4s; transform-origin: center; }
.theme-icon .moon { transition: transform .6s var(--ease-out), opacity .4s; transform-origin: center; }
:root[data-theme="dark"] .theme-icon .sun { opacity: 0; transform: rotate(-90deg) scale(.5); }
:root:not([data-theme="dark"]) .theme-icon .moon { opacity: 0; transform: rotate(90deg) scale(.5); }

/* Segmented language control */
.seg { position: relative; display: inline-grid; grid-auto-flow: column; grid-auto-columns: 1fr; padding: 4px; border-radius: 999px; }
.seg button {
  position: relative; z-index: 1; height: 38px; min-width: 44px; padding: 0 12px; border-radius: 999px;
  font: 13px/1 var(--font-ui); letter-spacing: .04em; color: var(--fg-dim); transition: color .3s;
}
.seg button[aria-pressed="true"] { color: var(--accent-ink); }
.seg__thumb {
  position: absolute; z-index: 0; top: 4px; bottom: 4px; left: 4px; border-radius: 999px; background: var(--accent);
  transition: transform .5s var(--ease-out), width .5s var(--ease-out);
}

/* =====================================================================
   DRAWER — slides out from the left
   ===================================================================== */
.scrim {
  position: fixed; inset: 0; z-index: 50; background: var(--scrim);
  opacity: 0; visibility: hidden; transition: opacity .6s var(--ease-out), visibility 0s linear .6s;
}
.scrim.is-on { opacity: 1; visibility: visible; transition: opacity .6s var(--ease-out); }
.drawer {
  position: fixed; z-index: 60; top: 12px; bottom: 12px; left: 12px; width: var(--drawer-w);
  display: flex; flex-direction: column; border-radius: calc(var(--radius) + 6px);
  padding: 22px 22px max(20px, env(safe-area-inset-bottom));
  transform: translateX(calc(-100% - 24px)); visibility: hidden;
  transition: transform .75s var(--ease-out), visibility 0s linear .75s;
  overflow: hidden auto; overscroll-behavior: contain;
  background: var(--glass-strong);
}
.drawer.is-open { transform: none; visibility: visible; transition: transform .75s var(--ease-out); }
.drawer__head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 28px; }
.drawer__brand { font: italic 26px/1 var(--font-display); }
.drawer__close { width: 42px; height: 42px; border-radius: 50%; display: grid; place-items: center; border: 1px solid var(--line); transition: transform .5s var(--ease-out), background-color .3s; }
.drawer__close:hover { transform: rotate(90deg); background: var(--fg-faint); }
.drawer__close svg { width: 16px; height: 16px; }

.nav { list-style: none; margin: 0; padding: 0; display: grid; gap: 2px; }
.nav a {
  position: relative; display: grid; grid-template-columns: 34px 1fr auto; align-items: center; gap: 8px;
  padding: 14px 12px; border-radius: 14px; transition: background-color .3s, padding .5s var(--ease-out);
}
.drawer.is-open .nav li { animation: navIn .8s var(--ease-out) both; animation-delay: calc(var(--i) * 60ms + 120ms); }
@keyframes navIn { from { opacity: 0; transform: translateX(-24px); } }
.nav a:hover { background: var(--fg-faint); padding-left: 18px; }
.nav__num { font: 12px/1 var(--font-ui); color: var(--fg-dim); letter-spacing: .08em; font-variant-numeric: tabular-nums; }
.nav__label { font-family: var(--font-display); font-size: 24px; line-height: 1.2; }
:root:lang(en) .nav__label { font-style: italic; }
.nav__sub { display: block; font: 12px/1.4 var(--font-ui); color: var(--fg-dim); letter-spacing: .04em; font-style: normal; }
.nav__arrow { width: 18px; height: 18px; opacity: 0; transform: translateX(-8px); transition: opacity .3s, transform .5s var(--ease-out); }
.nav a:hover .nav__arrow, .nav a[aria-current="true"] .nav__arrow { opacity: 1; transform: none; }
/* active section indicator + reading progress inside the drawer */
.nav a::before {
  content: ""; position: absolute; left: 0; top: 18px; bottom: 18px; width: 2px; border-radius: 2px;
  background: var(--accent); transform: scaleY(0); transition: transform .5s var(--ease-out);
}
.nav a[aria-current="true"]::before { transform: scaleY(1); }
.nav a[aria-current="true"] .nav__num { color: var(--accent); }

.drawer__section { margin-top: auto; padding-top: 24px; display: grid; gap: 14px; }
.drawer__row { display: flex; align-items: center; justify-content: space-between; gap: 12px; font: 12px/1 var(--font-ui); letter-spacing: .14em; text-transform: uppercase; color: var(--fg-dim); }
.drawer__row .seg { background: var(--fg-faint); }
.switch {
  position: relative; width: 58px; height: 32px; border-radius: 999px; background: var(--fg-faint);
  transition: background-color .4s;
}
.switch::after {
  content: ""; position: absolute; top: 4px; left: 4px; width: 24px; height: 24px; border-radius: 50%;
  background: var(--fg); transition: transform .5s var(--ease-spring);
}
.switch[aria-checked="true"] { background: var(--accent); }
.switch[aria-checked="true"]::after { transform: translateX(26px); background: var(--accent-ink); }
.drawer__foot { padding-top: 18px; border-top: 1px solid var(--line); font: 12px/1.6 var(--font-ui); color: var(--fg-dim); }

/* =====================================================================
   PAGE STRUCTURE
   ===================================================================== */
main { position: relative; z-index: 2; }
.section { position: relative; padding: clamp(96px, 14vh, 160px) var(--gutter); }
.wrap { max-width: 1240px; margin: 0 auto; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 12px;
  font: 12px/1 var(--font-ui); letter-spacing: .22em; text-transform: uppercase; color: var(--fg-dim);
}
.eyebrow::before { content: ""; width: 28px; height: 1px; background: currentColor; }
.h2 { margin: 18px 0 0; font-family: var(--font-display); font-weight: 400; font-size: clamp(40px, 6vw, 84px); line-height: 1.02; letter-spacing: -.01em; }
.h2 em { color: var(--accent); }
.lead { max-width: 62ch; color: var(--fg-dim); font-size: clamp(16px, 1.3vw, 19px); }
.placeholder { border-bottom: 1px dashed var(--fg-faint); }

/* Reveal on scroll */
.reveal { opacity: 0; transform: translateY(40px); transition: opacity 1s var(--ease-out), transform 1.2s var(--ease-out); transition-delay: calc(var(--d, 0) * 90ms); }
.reveal.is-in { opacity: 1; transform: none; }

/* Buttons */
.btn {
  position: relative; display: inline-flex; align-items: center; gap: 12px; height: 52px; padding: 0 26px; border-radius: 999px;
  font: 14px/1 var(--font-ui); letter-spacing: .08em; overflow: hidden; isolation: isolate;
  transition: transform .5s var(--ease-out), color .4s;
}
.btn svg { width: 18px; height: 18px; transition: transform .5s var(--ease-out); }
.btn:hover svg { transform: translateX(4px); }
.btn--solid { background: var(--fg); color: var(--bg); }
.btn--solid::before {
  content: ""; position: absolute; inset: 0; z-index: -1; background: var(--accent);
  transform: translateY(101%); border-radius: 50% 50% 0 0; transition: transform .6s var(--ease-out), border-radius .6s var(--ease-out);
}
.btn--solid:hover { color: var(--accent-ink); }
.btn--solid:hover::before { transform: none; border-radius: 0; }
.btn--ghost { border: 1px solid var(--line); }
.btn--ghost:hover { background: var(--fg-faint); }

/* =====================================================================
   ACCORDION — rows with a › arrow that expand a panel
   ===================================================================== */
.acc { border-top: 1px solid var(--line); }
.acc__item { border-bottom: 1px solid var(--line); }
.acc__btn {
  width: 100%; display: grid; grid-template-columns: 44px 1fr 40px; align-items: center; gap: 12px;
  padding: 22px 4px; text-align: left; transition: padding .5s var(--ease-out);
}
.acc__btn:hover { padding-left: 12px; }
.acc__num { font: 12px/1 var(--font-ui); color: var(--fg-dim); letter-spacing: .08em; }
.acc__title { font-family: var(--font-display); font-size: clamp(22px, 2.2vw, 30px); line-height: 1.2; }
:root:lang(en) .acc__title { font-style: italic; }
.acc__chev {
  width: 40px; height: 40px; border-radius: 50%; display: grid; place-items: center; border: 1px solid var(--line);
  transition: transform .6s var(--ease-out), background-color .3s, border-color .3s;
}
.acc__chev svg { width: 16px; height: 16px; }
.acc__btn[aria-expanded="true"] .acc__chev { transform: rotate(90deg); background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.acc__panel { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .7s var(--ease-out); }
.acc__panel > div { overflow: hidden; }
.acc__btn[aria-expanded="true"] + .acc__panel { grid-template-rows: 1fr; }
.acc__body { padding: 0 4px 28px 60px; color: var(--fg-dim); }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.chip {
  display: inline-flex; align-items: center; height: 34px; padding: 0 14px; border-radius: 999px;
  border: 1px solid var(--line); font: 13px/1 var(--font-ui); letter-spacing: .02em; color: var(--fg);
  transition: background-color .3s, border-color .3s, color .3s, transform .4s var(--ease-out);
}
.chip:hover { transform: translateY(-2px); border-color: var(--fg-dim); }
.chip[aria-pressed="true"] { background: var(--fg); color: var(--bg); border-color: var(--fg); }

/* =====================================================================
   SHOWCASE — category dropdown, hover list, preview, dial
   ===================================================================== */
.filter { position: relative; display: inline-block; }
.filter__btn {
  display: inline-flex; align-items: center; gap: 12px; height: 46px; padding: 0 10px 0 18px; border-radius: 999px;
  font: 13px/1 var(--font-ui); letter-spacing: .06em;
}
.filter__btn b { font-weight: 600; color: var(--accent); }
.filter__btn .acc__chev { width: 30px; height: 30px; }
.filter__btn[aria-expanded="true"] .acc__chev { transform: rotate(90deg); }
.filter__pop {
  position: absolute; z-index: 20; top: calc(100% + 10px); right: 0; width: min(300px, calc(100vw - 32px)); padding: 14px; border-radius: var(--radius);
  background: var(--glass-strong);
  opacity: 0; visibility: hidden; transform: translateY(-8px) scale(.98); transform-origin: top right;
  transition: opacity .35s var(--ease-out), transform .5s var(--ease-out), visibility 0s linear .5s;
}
.filter__pop.is-open { opacity: 1; visibility: visible; transform: none; transition: opacity .35s var(--ease-out), transform .5s var(--ease-out); }
.filter__pop .chips { margin: 0; }
.filter__hint { margin: 0 0 10px; font: 11px/1 var(--font-ui); letter-spacing: .16em; text-transform: uppercase; color: var(--fg-dim); }

.show { display: grid; gap: clamp(24px, 4vw, 56px); margin-top: 40px; }
.show__list { list-style: none; margin: 0; padding: 0; }
.show__item { border-bottom: 1px solid var(--line); }
.show__item:first-child { border-top: 1px solid var(--line); }
.show__item[hidden] { display: none; }
.show__link {
  position: relative; width: 100%; display: grid; grid-template-columns: 44px 1fr auto; align-items: baseline; gap: 12px;
  padding: 20px 4px; text-align: left; transition: padding .5s var(--ease-out), color .3s;
  color: var(--fg-dim);
}
.show__link:hover, .show__item.is-active .show__link { color: var(--fg); padding-left: 16px; }
.show__num { font: 12px/1 var(--font-ui); letter-spacing: .08em; font-variant-numeric: tabular-nums; }
.show__name { font-family: var(--font-display); font-size: clamp(24px, 2.6vw, 38px); line-height: 1.15; }
:root:lang(en) .show__name { font-style: italic; }
.show__tag { font: 12px/1 var(--font-ui); letter-spacing: .1em; text-transform: uppercase; }
.show__item.is-active .show__tag { color: var(--accent); }
.show__link::after {
  content: ""; position: absolute; left: 0; bottom: -1px; height: 1px; width: 100%; background: var(--fg);
  transform: scaleX(0); transform-origin: left; transition: transform .7s var(--ease-out);
}
.show__item.is-active .show__link::after { transform: scaleX(1); }

.stage { position: relative; }
.stage__frame {
  position: relative; aspect-ratio: 4 / 3; border-radius: var(--radius); overflow: hidden; isolation: isolate;
  background: var(--fg-faint);
}
.stage__slide {
  position: absolute; inset: 0; clip-path: inset(0 0 0 100%); transition: clip-path 1s var(--ease-in-out);
}
.stage__slide.is-active { clip-path: inset(0 0 0 0); z-index: 2; }
.stage__slide.is-leaving { clip-path: inset(0 0 0 0); z-index: 1; }
.stage__slide svg { width: 100%; height: 100%; transform: scale(1.12); transition: transform 1.6s var(--ease-out); }
.stage__slide.is-active svg { transform: scale(1); }
.stage__cap {
  position: absolute; z-index: 3; left: 16px; right: 16px; bottom: 16px; display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px 10px 10px 18px; border-radius: 999px;
}
.stage__title { font: italic 18px/1.2 var(--font-display); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
:root:lang(zh-CN) .stage__title, :root:lang(zh-TW) .stage__title { font-style: normal; }
.stage__open { height: 40px; padding: 0 16px; font-size: 13px; }

/* Dial / knob */
.dialbar { display: flex; align-items: center; justify-content: space-between; gap: 18px; margin-top: 20px; }
.dial {
  --angle: 0deg; position: relative; width: 112px; height: 112px; flex: none; border-radius: 50%;
  touch-action: none; cursor: grab; user-select: none;
}
.dial:active { cursor: grabbing; }
.dial__ticks { position: absolute; inset: 0; }
.dial__tick { position: absolute; left: 50%; top: 50%; width: 2px; height: 8px; margin: -4px 0 0 -1px; border-radius: 2px; background: var(--fg-dim); transition: background-color .3s, height .3s; }
.dial__tick--minor { width: 1px; height: 4px; margin: -2px 0 0 -.5px; background: var(--fg-faint); }
.dial__tick--major { opacity: .7; }
.dial__tick.is-on { background: var(--accent); opacity: 1; }
.dial__knob {
  position: absolute; inset: 16px; border-radius: 50%; transform: rotate(var(--angle));
  background: radial-gradient(120% 120% at 30% 20%, var(--glass-hi), transparent 60%), var(--glass-strong);
  border: 1px solid var(--glass-brd);
  box-shadow: inset 0 -6px 14px rgba(0,0,0,.12), 0 14px 30px -12px rgba(0,0,0,.45);
  transition: transform .6s var(--ease-spring);
}
.dial.is-dragging .dial__knob { transition: none; }
.dial__knob::before { content: ""; position: absolute; left: 50%; top: 9px; width: 4px; height: 16px; margin-left: -2px; border-radius: 4px; background: var(--accent); }
.dial__knob::after { content: ""; position: absolute; inset: 30%; border-radius: 50%; border: 1px solid var(--line); }
.dial__readout { font: 12px/1.6 var(--font-ui); letter-spacing: .14em; text-transform: uppercase; color: var(--fg-dim); }
.dial__readout b { display: block; font: italic 40px/1 var(--font-display); letter-spacing: 0; color: var(--fg); font-variant-numeric: tabular-nums; }
.stepper { display: flex; gap: 8px; }
.stepper button { width: 46px; height: 46px; border-radius: 50%; display: grid; place-items: center; border: 1px solid var(--line); transition: background-color .3s, transform .4s var(--ease-out); }
.stepper button:hover { background: var(--fg-faint); }
.stepper button:active { transform: scale(.94); }
.stepper svg { width: 18px; height: 18px; }

/* =====================================================================
   DETAIL PANEL — always with a clear ← back button
   ===================================================================== */
.detail {
  position: fixed; z-index: 70; inset: 0; display: grid; grid-template-rows: auto 1fr;
  background: var(--bg); overflow: hidden auto; overscroll-behavior: contain;
  clip-path: inset(0 0 0 100%); visibility: hidden;
  transition: clip-path .9s var(--ease-in-out), visibility 0s linear .9s;
}
.detail.is-open { clip-path: inset(0 0 0 0); visibility: visible; transition: clip-path .9s var(--ease-in-out); }
.detail__bar {
  position: sticky; top: 0; z-index: 2; display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 14px var(--gutter); background: color-mix(in srgb, var(--bg) 80%, transparent);
  -webkit-backdrop-filter: blur(16px); backdrop-filter: blur(16px); border-bottom: 1px solid var(--line);
}
.back {
  display: inline-flex; align-items: center; gap: 12px; height: 46px; padding: 0 20px 0 8px; border-radius: 999px;
  border: 1px solid var(--line); font: 14px/1 var(--font-ui); letter-spacing: .06em; transition: background-color .3s;
}
.back:hover { background: var(--fg-faint); }
.back__ico { width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center; background: var(--fg); color: var(--bg); transition: transform .5s var(--ease-out); }
.back:hover .back__ico { transform: translateX(-4px); }
.back svg { width: 16px; height: 16px; }
.detail__crumb { font: 12px/1 var(--font-ui); letter-spacing: .14em; text-transform: uppercase; color: var(--fg-dim); }
.detail__body { padding: clamp(32px, 6vw, 80px) var(--gutter) 96px; max-width: 1100px; width: 100%; margin: 0 auto; }
:root:lang(en) .detail__title { font-style: italic; }
.detail__hero { aspect-ratio: 16 / 7; border-radius: var(--radius); overflow: hidden; margin: 28px 0 40px; }
.detail__hero svg { width: 100%; height: 100%; }
.detail__grid { display: grid; gap: 32px; }
.meta { display: grid; gap: 16px; align-content: start; font: 13px/1.6 var(--font-ui); color: var(--fg-dim); }
.meta dt { letter-spacing: .14em; text-transform: uppercase; font-size: 11px; }
.meta dd { margin: 2px 0 0; color: var(--fg); font-size: 15px; }
.detail .is-open-anim { animation: rise 1s var(--ease-out) both .35s; }
@keyframes rise { from { opacity: 0; transform: translateY(30px); } }

/* =====================================================================
   DIRECTION SWITCHER (prototype only)
   ===================================================================== */
.dirs {
  position: fixed; z-index: 45; left: 50%; top: 13px; transform: translateX(-50%);
  display: flex; align-items: center; gap: 4px; padding: 5px; border-radius: 999px;
  font: 12px/1 var(--font-ui);
}
.dirs span { padding: 0 8px 0 10px; letter-spacing: .14em; text-transform: uppercase; color: var(--fg-dim); }
.dirs a { width: 34px; height: 34px; border-radius: 50%; display: grid; place-items: center; font-weight: 600; transition: background-color .3s, color .3s; }
.dirs a:hover { background: var(--fg-faint); }
.dirs a[aria-current="page"] { background: var(--fg); color: var(--bg); }

/* Footer */
.foot { position: relative; z-index: 2; padding: 32px var(--gutter) 96px; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; font: 12px/1.6 var(--font-ui); letter-spacing: .08em; color: var(--fg-dim); border-top: 1px solid var(--line); }

/* =====================================================================
   RESPONSIVE
   ===================================================================== */
@media (min-width: 900px) {
  .show { grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr); align-items: start; }
  .stage { position: sticky; top: 96px; }
  .detail__grid { grid-template-columns: 1fr 2.2fr; }
}
@media (max-width: 640px) {
  :root { --topbar-h: 64px; }
  body { font-size: 16px; }
  .menu-btn__label { display: none; }
  .menu-btn { padding: 0 8px; }
  .topbar .seg { display: none; }
  .acc__btn { grid-template-columns: 32px 1fr 40px; }
  .acc__body { padding-left: 4px; }
  .show__link { grid-template-columns: 32px 1fr; }
  .show__tag { grid-column: 2; }
  .dial { width: 96px; height: 96px; }
  .dirs span { display: none; }
  .filter__pop { right: auto; left: 0; transform-origin: top left; }
}
@media (hover: none) {
  .show__link:hover { padding-left: 4px; color: var(--fg-dim); }
}

/* Motion preferences */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; transition-delay: 0s !important; }
  html { scroll-behavior: auto; }
}

/* Language swap + theme cross-fade helpers */
main, .drawer .nav, .foot { transition: opacity .25s ease; }
:root.is-swapping main, :root.is-swapping .drawer .nav, :root.is-swapping .foot { opacity: 0; }
:root.is-theming *, :root.is-theming *::before, :root.is-theming *::after {
  transition-property: background-color, color, border-color, fill, stroke, opacity, box-shadow, transform, clip-path, grid-template-rows !important;
  transition-duration: .8s !important;
}

/* =====================================================================
   FUNCTIONAL LAYER — search button, command palette, toast,
   status panel, copy buttons (see shared/features.js)
   ===================================================================== */
kbd {
  display: inline-flex; align-items: center; justify-content: center; min-width: 22px; height: 22px; padding: 0 6px;
  border-radius: 6px; border: 1px solid var(--line); border-bottom-width: 2px;
  font: 500 11px/1 var(--font-ui); letter-spacing: 0; color: var(--fg-dim); background: color-mix(in srgb, var(--bg) 60%, transparent);
}
.search-btn {
  display: inline-flex; align-items: center; gap: 10px; height: 46px; padding: 0 8px 0 16px; border-radius: 999px;
  font: 13px/1 var(--font-ui); letter-spacing: .04em; color: var(--fg-dim); transition: color .3s, transform .4s var(--ease-out);
}
.search-btn:hover { color: var(--fg); transform: translateY(-1px); }
.search-btn svg { width: 17px; height: 17px; }

.cmd { position: fixed; inset: 0; z-index: 90; display: grid; justify-items: center; align-items: start; padding: min(14vh, 120px) 16px 16px; visibility: hidden; }
.cmd.is-open { visibility: visible; }
.cmd__scrim { position: absolute; inset: 0; background: var(--scrim); opacity: 0; transition: opacity .35s var(--ease-out); }
.cmd.is-open .cmd__scrim { opacity: 1; }
.cmd__box {
  position: relative; width: min(640px, 100%); max-height: min(70vh, 560px); display: grid; grid-template-rows: auto 1fr auto;
  border-radius: 20px; background: var(--glass-strong); overflow: hidden;
  opacity: 0; transform: translateY(-10px) scale(.985); transition: opacity .3s var(--ease-out), transform .45s var(--ease-out);
}
.cmd.is-open .cmd__box { opacity: 1; transform: none; }
.cmd__field { display: flex; align-items: center; gap: 12px; padding: 16px 18px; border-bottom: 1px solid var(--line); color: var(--fg-dim); }
.cmd__field svg { width: 20px; height: 20px; flex: none; }
.cmd__input { flex: 1; min-width: 0; border: 0; outline: 0; background: none; color: var(--fg); font: 17px/1.4 var(--font-body); }
.cmd__input::placeholder { color: var(--fg-dim); }
.cmd__list { list-style: none; margin: 0; padding: 8px; overflow: auto; overscroll-behavior: contain; }
.cmd__group { padding: 12px 12px 6px; font: 11px/1 var(--font-ui); letter-spacing: .16em; text-transform: uppercase; color: var(--fg-dim); }
.cmd__item { display: grid; grid-template-columns: 34px 1fr auto; align-items: center; gap: 10px; padding: 9px 12px; border-radius: 12px; cursor: pointer; }
.cmd__item.is-sel { background: var(--fg-faint); }
.cmd__ico { width: 34px; height: 34px; display: grid; place-items: center; border-radius: 10px; border: 1px solid var(--line); color: var(--fg-dim); }
.cmd__item.is-sel .cmd__ico { color: var(--accent); border-color: color-mix(in srgb, var(--accent) 45%, transparent); }
.cmd__ico svg { width: 18px; height: 18px; }
.cmd__txt { display: grid; min-width: 0; }
.cmd__txt b { font-weight: 500; font-size: 15px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.cmd__txt small { font: 12px/1.4 var(--font-ui), var(--font-zh-sans); color: var(--fg-dim); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.cmd__empty { padding: 28px; text-align: center; color: var(--fg-dim); }
.cmd__foot { margin: 0; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 6px 16px; padding: 10px 16px; border-top: 1px solid var(--line); font: 12px/1.6 var(--font-ui), var(--font-zh-sans); color: var(--fg-dim); }
.cmd__foot kbd { height: 20px; min-width: 20px; font-size: 10px; }

.toast {
  position: fixed; z-index: 95; left: 50%; bottom: max(28px, env(safe-area-inset-bottom)); transform: translate(-50%, 16px);
  padding: 12px 20px; border-radius: 999px; background: var(--fg); color: var(--bg); font: 14px/1.2 var(--font-ui), var(--font-zh-sans);
  box-shadow: var(--shadow); opacity: 0; pointer-events: none; transition: opacity .3s, transform .5s var(--ease-out);
}
.toast.is-on { opacity: 1; transform: translate(-50%, 0); }

.status {
  position: fixed; z-index: 80; left: var(--gutter); bottom: max(18px, env(safe-area-inset-bottom)); width: min(360px, calc(100vw - 32px));
  padding: 18px 18px 8px; border-radius: 20px; background: var(--glass-strong);
  opacity: 0; transform: translateY(12px); visibility: hidden; transition: opacity .3s, transform .5s var(--ease-out), visibility 0s linear .5s;
}
.status.is-open { opacity: 1; transform: none; visibility: visible; transition: opacity .3s, transform .5s var(--ease-out); }
.status__head { display: flex; justify-content: space-between; align-items: start; gap: 12px; margin-bottom: 10px; }
.status__head b { display: block; font-weight: 500; font-size: 16px; }
.status__head small { font: 12px/1.5 var(--font-ui), var(--font-zh-sans); color: var(--fg-dim); }
.status__x { width: 32px; height: 32px; border-radius: 50%; display: grid; place-items: center; border: 1px solid var(--line); flex: none; }
.status__x svg { width: 12px; height: 12px; }
.status__grid { margin: 0; }
.status__row { display: flex; justify-content: space-between; gap: 12px; padding: 9px 0; border-top: 1px solid var(--line); font: 13px/1.4 var(--font-ui), var(--font-zh-sans); }
.status__row dt { color: var(--fg-dim); }
.status__row dd { margin: 0; font-variant-numeric: tabular-nums; text-align: right; }

.foot__status { display: inline-flex; align-items: center; gap: 8px; font: inherit; letter-spacing: inherit; color: inherit; }
.foot__status:hover { color: var(--fg); }
.foot__dot { width: 7px; height: 7px; border-radius: 50%; background: #3fb27f; box-shadow: 0 0 0 3px color-mix(in srgb, #3fb27f 25%, transparent); }
.copy-btn { gap: 6px; cursor: pointer; }
.copy-btn svg { width: 15px; height: 15px; }
.contact__mail + .copy-btn { vertical-align: middle; margin-left: 10px; }
.detail__bar .copy-btn { margin-left: 12px; }
.detail__bar { justify-content: flex-start; }
.detail__bar .detail__crumb { margin-left: auto; }

@media (max-width: 640px) {
  .search-btn { width: 46px; padding: 0; justify-content: center; }
  .search-btn span, .search-btn kbd { display: none; }
  .cmd { padding-top: 72px; }
  .cmd__foot .cmd__keys { display: none; }
  .detail__bar .detail__crumb { display: none; }
}
@media (hover: none) { .search-btn kbd { display: none; } }

/* Hero "next" arrow — a clear, clickable way down */
.hero__next {
  position: absolute; left: 0; right: 0; bottom: max(26px, env(safe-area-inset-bottom)); margin: 0 auto; z-index: 3;
  width: 58px; height: 58px; border-radius: 50%; display: grid; place-items: center; color: var(--fg);
  background: var(--glass); border: 1px solid var(--glass-brd); box-shadow: inset 0 1px 0 var(--glass-hi), var(--shadow);
  -webkit-backdrop-filter: blur(16px) saturate(150%); backdrop-filter: blur(16px) saturate(150%);
  transition: background-color .3s, transform .5s var(--ease-out);
}
.hero__next svg { width: 22px; height: 22px; animation: nudge 2.4s var(--ease-in-out) infinite; }
.hero__next:hover { background: var(--glass-strong); transform: translateY(3px); }
@keyframes nudge { 0%, 100% { transform: translateY(-2px); } 50% { transform: translateY(4px); } }