/* ============ Fonts (self-hosted) ============ */
@font-face { font-family: "Instrument Serif"; src: url("assets/fonts/instrument-serif.woff2") format("woff2"); font-weight: 400; font-style: normal; font-display: swap; }
@font-face { font-family: "Instrument Serif"; src: url("assets/fonts/instrument-serif-italic.woff2") format("woff2"); font-weight: 400; font-style: italic; font-display: swap; }
@font-face { font-family: "Geist"; src: url("assets/fonts/geist-latin.woff2") format("woff2"); font-weight: 300 700; font-display: swap; }
@font-face { font-family: "Geist Mono"; src: url("assets/fonts/geist-mono-latin.woff2") format("woff2"); font-weight: 400 500; font-display: swap; }

/* ============ Tokens ============ */
:root {
  --bg: #f3eee6;        /* bone */
  --paper: #faf7f2;
  --sand: #e8dfd1;
  --ink: #1b1814;
  --ink-2: #5e574e;
  --ink-3: #978e82;
  --line: rgba(27, 24, 20, .12);
  --night: #13110e;
  --on-night: #efe7da;
  --on-night-2: #a39a8c;
  --max: 1240px;
  --gutter: clamp(20px, 5vw, 56px);
  --ease: cubic-bezier(.22, .61, .21, 1);
  --serif: "Instrument Serif", "Iowan Old Style", "Times New Roman", serif;
  --sans: "Geist", -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "Geist Mono", ui-monospace, "SF Mono", Menlo, monospace;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 60px; background: var(--bg); }
body {
  margin: 0;
  overflow-x: clip;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4, h5, p, ol, ul, dl, dd, figure { margin: 0; }
ol, ul { padding: 0; list-style: none; }
:focus-visible { outline: 2px solid currentColor; outline-offset: 3px; border-radius: 4px; }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }

.serif { font-family: var(--serif); font-weight: 400; letter-spacing: -.01em; }
.serif em { font-style: italic; }
.mono, .label { font-family: var(--mono); font-size: 12px; font-weight: 400; letter-spacing: .08em; text-transform: uppercase; }
.label { display: block; margin-bottom: 24px; color: var(--ink-3); }

/* ============ Header ============ */
.site-header { position: fixed; z-index: 50; inset: 0 0 auto; height: 60px; transition: background-color .4s, box-shadow .4s, color .4s; }
.site-header.is-scrolled { background: rgba(243, 238, 230, .8); box-shadow: 0 1px 0 var(--line); -webkit-backdrop-filter: saturate(1.4) blur(20px); backdrop-filter: saturate(1.4) blur(20px); }
.site-header.on-dark { color: var(--on-night); }
.site-header.on-dark.is-scrolled { background: rgba(19, 17, 14, .72); box-shadow: 0 1px 0 rgba(255, 255, 255, .08); }
.header-inner { height: 100%; max-width: var(--max); margin: 0 auto; padding: 0 var(--gutter); display: flex; align-items: center; gap: 40px; }
.brand { display: inline-flex; align-items: center; gap: 10px; }
.wordmark { font-family: var(--serif); font-size: 27px; font-weight: 400; line-height: 1; letter-spacing: -.01em; transform: translateY(1px); }
.wordmark em { font-style: italic; }
.nav { display: flex; gap: 30px; margin-left: auto; font-size: 14px; }
.nav a { opacity: .6; transition: opacity .2s; }
.nav a:hover { opacity: 1; }
.nav-cta { padding: 8px 16px; border-radius: 99px; background: var(--ink); color: var(--bg); font-size: 13px; font-weight: 500; transition: background-color .3s, color .3s; }
.on-dark .nav-cta { background: var(--on-night); color: var(--ink); }

/* Language switch */
.lang { display: flex; align-items: center; margin-left: -12px; font-size: 13px; }
.lang button { position: relative; padding: 6px 7px; border: 0; background: none; color: inherit; font: inherit; opacity: .45; cursor: pointer; transition: opacity .2s; }
.lang button + button::before { content: ""; position: absolute; left: -1px; top: 50%; width: 1px; height: 11px; background: currentColor; opacity: .35; transform: translateY(-50%); }
.lang button:hover { opacity: .8; }
.lang button[aria-pressed="true"] { opacity: 1; cursor: default; }
.lang button[lang="zh-CN"] { font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", var(--sans); }

/* Copy swap when switching language */
.i18n-wait body { opacity: 0; }
main, .site-footer, .nav, .nav-cta, .dock-btn { transition: opacity .22s ease; }
.is-switching :is(main, .site-footer, .nav, .nav-cta, .dock-btn) { opacity: 0; }

/* ============ Buttons ============ */
.cta-row { display: flex; flex-wrap: wrap; gap: 12px; }
.btn { white-space: nowrap; display: inline-flex; align-items: center; justify-content: center; height: 52px; padding: 0 28px; border-radius: 99px; font-size: 15px; font-weight: 500; transition: background-color .25s, color .25s, box-shadow .25s, transform .25s var(--ease); }
.btn:active { transform: scale(.98); }
.btn-dark { background: var(--ink); color: var(--bg); }
.btn-dark:hover { background: #38322b; }
.btn-ghost { box-shadow: inset 0 0 0 1px rgba(27, 24, 20, .28); }
.btn-ghost:hover { box-shadow: inset 0 0 0 1px var(--ink); }
/* Android visitors get their platform first */
.is-android [data-cta-group] [data-platform="android"] { order: -1; }
.is-android :is(.hero, .download) [data-platform="android"] { background: var(--ink); color: var(--bg); box-shadow: none; }
.is-android :is(.hero, .download) [data-platform="ios"] { background: none; color: var(--ink); box-shadow: inset 0 0 0 1px rgba(27, 24, 20, .28); }

/* ============ Hero ============ */
.hero { position: relative; overflow: hidden; height: 100svh; min-height: 640px; max-height: 1100px; }
.hero-media { position: absolute; inset: 0; will-change: transform; }
.hero-media img { width: 100%; height: 100%; object-fit: cover; object-position: 70% 50%; }
/* soften the stone behind the headline */
.hero::after { content: ""; position: absolute; inset: 0; pointer-events: none; background: linear-gradient(90deg, rgba(243, 238, 230, .9) 0%, rgba(243, 238, 230, .72) 30%, rgba(243, 238, 230, 0) 58%), linear-gradient(0deg, rgba(243, 238, 230, .35), transparent 30%); }
.hero-copy { position: absolute; z-index: 1; left: max(var(--gutter), calc((100vw - var(--max)) / 2 + var(--gutter))); bottom: clamp(56px, 11vh, 120px); width: min(620px, 46vw); }
.hero h1 { font-size: clamp(64px, 7.4vw, 118px); line-height: .92; letter-spacing: -.025em; }
.hero-lead { max-width: 430px; margin: 28px 0 36px; font-size: 18px; line-height: 1.5; color: var(--ink-2); }
.js .hero-media img { animation: heroIn 14s cubic-bezier(.16, .6, .2, 1) both; }
.js .hero-copy > * { animation: fadeUp 1.1s .2s var(--ease) both; }
.js .hero-copy > :nth-child(2) { animation-delay: .3s; }
.js .hero-copy > :nth-child(3) { animation-delay: .45s; }
.js .hero-copy > :nth-child(4) { animation-delay: .55s; }
@keyframes heroIn { from { transform: scale(1.12); } }
@keyframes fadeUp { from { opacity: 0; transform: translateY(18px); } }

/* ============ Manifesto ============ */
.manifesto { max-width: var(--max); margin: 0 auto; padding: clamp(120px, 16vw, 240px) var(--gutter); }
.manifesto p { max-width: 1000px; font-size: clamp(40px, 5.4vw, 84px); line-height: 1.02; letter-spacing: -.02em; color: var(--ink-3); }
.manifesto em { color: var(--ink); }

/* ============ The object ============ */
.split { display: grid; grid-template-columns: 7fr 5fr; align-items: center; min-height: min(100svh, 980px); }
.split-media { position: relative; height: 100%; min-height: min(100svh, 980px); overflow: hidden; }
.split-media img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; transform: scale(var(--z, 1)); will-change: transform; }
.split-copy { max-width: 440px; padding: 80px var(--gutter); justify-self: center; }
.split-copy h3, .wide-copy h3 { font-size: clamp(44px, 4.8vw, 76px); line-height: .98; letter-spacing: -.02em; }
.split-copy > p:last-child, .wide-copy > p:last-child { margin-top: 24px; font-size: 17px; color: var(--ink-2); }
.split-night { grid-template-columns: 5fr 7fr; background: var(--night); color: var(--on-night); }
.split-night .label, .split-night .split-copy > p:last-child { color: var(--on-night-2); }
.split-night .split-copy em { color: #d9b98a; }
.split-night .split-media img { object-position: 50% 0; transform-origin: 50% 0; }

.wide-media { overflow: hidden; aspect-ratio: 1916 / 821; max-height: 100svh; }
.wide-media img { width: 100%; height: 100%; object-fit: cover; transform: scale(var(--z, 1)); will-change: transform; }
.wide-copy { max-width: var(--max); margin: 0 auto; padding: 56px var(--gutter) 0; display: grid; grid-template-columns: 7fr 4fr; gap: 0 clamp(32px, 6vw, 96px); align-items: end; }
.wide-copy .label { grid-column: 1 / -1; }
.wide-copy > p:last-child { margin: 0 0 6px; }

/* ============ How it works ============ */
.how { position: relative; height: 340vh; margin-top: clamp(100px, 12vw, 180px); }
.how-sticky { position: sticky; top: 0; height: 100svh; max-width: var(--max); margin: 0 auto; padding: 96px var(--gutter) 48px; display: grid; grid-template-columns: 5fr 6fr; gap: clamp(32px, 6vw, 96px); align-items: center; }
.how-media { height: min(76svh, 720px); }
.how-media img { width: 100%; height: 100%; object-fit: cover; }
.how-copy h2 { font-size: clamp(44px, 4.6vw, 72px); line-height: .96; letter-spacing: -.02em; margin-bottom: 40px; }

.sheet { position: relative; padding: 22px 0 0; border-top: 1px solid var(--ink); }
.sheet-head { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 20px; font-weight: 500; }
.sheet-head .mono { color: var(--ink-3); transition: color .4s; }
.sheet-head .mono.is-rec { color: #b5452f; }
.sheet-body { position: relative; height: 270px; }
.sheet-timer { display: none; }
.js .sheet-timer { display: block; position: absolute; left: 0; top: 0; font-size: clamp(96px, 10vw, 150px); line-height: 1; letter-spacing: -.02em; font-variant-numeric: tabular-nums; transition: opacity .5s var(--ease), transform .5s var(--ease); }
.js .sheet.is-text .sheet-timer { opacity: 0; transform: translateY(-10px); }
.transcript, .summary { position: absolute; inset: 0; transition: opacity .6s var(--ease), transform .6s var(--ease), filter .6s var(--ease); }
.t-line { display: grid; grid-template-columns: 82px 52px 1fr; gap: 0 8px; margin-bottom: 14px; font-size: 15px; line-height: 1.5; color: var(--ink-2); }
.t-line b { font-weight: 500; font-size: 13px; color: var(--ink); padding-top: 1px; }
.t-line .mono { padding-top: 3px; font-size: 11px; letter-spacing: .02em; color: var(--ink-3); }
.js .t-line { opacity: 0; transform: translateY(8px); transition: opacity .5s var(--ease), transform .5s var(--ease); }
.js .t-line.is-on { opacity: 1; transform: none; }
.summary .mono { color: var(--ink-3); margin-bottom: 10px; }
.summary ul { display: grid; gap: 6px; margin-bottom: 24px; }
.summary li { position: relative; padding-left: 20px; font-size: 16px; }
.summary li::before { content: ""; position: absolute; left: 4px; top: .65em; width: 5px; height: 5px; border-radius: 50%; background: var(--ink); }
.summary .todo li::before { top: .4em; left: 0; width: 11px; height: 11px; border-radius: 2px; background: none; box-shadow: inset 0 0 0 1.4px var(--ink-3); }
.js .summary { opacity: 0; transform: translateY(12px); pointer-events: none; }
.js .sheet.is-summary .transcript { opacity: 0; transform: translateY(-12px) scale(.98); filter: blur(4px); }
.js .sheet.is-summary .summary { opacity: 1; transform: none; }

.steps { display: grid; grid-template-columns: repeat(4, 1fr); margin-top: 32px; font-size: 14px; }
.steps li { position: relative; padding-top: 14px; color: var(--ink-3); transition: color .4s; }
.steps li::before { content: ""; position: absolute; left: 0; right: 8px; top: 0; height: 2px; background: var(--line); }
.steps li::after { content: ""; position: absolute; left: 0; right: 8px; top: 0; height: 2px; background: var(--ink); transform: scaleX(var(--fill, 0)); transform-origin: left; }
.steps .mono { display: block; margin-bottom: 2px; font-size: 11px; }
.steps li.is-active, .steps li.is-done { color: var(--ink); }

html:not(.js) .how { height: auto; }
html:not(.js) .how-sticky { position: static; height: auto; }
html:not(.js) .sheet-body { height: auto; }
html:not(.js) .transcript, html:not(.js) .summary { position: static; }
html:not(.js) .summary { margin-top: 24px; }

/* ============ Sections ============ */
.section { max-width: var(--max); margin: 0 auto; padding: clamp(110px, 13vw, 190px) var(--gutter) 0; }
.section-head { margin-bottom: clamp(48px, 6vw, 88px); }
.section-head h2, .download h2 { font-size: clamp(48px, 5.6vw, 88px); line-height: .96; letter-spacing: -.02em; }
.section-head h2 em { color: var(--ink-3); }

/* ============ Placeholders ============ */
.ph { position: relative; background: linear-gradient(160deg, #e7ddcd, #d6c9b5); }
.ph::after { content: attr(data-ph); position: absolute; left: 50%; top: 50%; width: 80%; transform: translate(-50%, -50%); text-align: center; font-family: var(--mono); font-size: 11px; line-height: 1.6; letter-spacing: .04em; color: #8d8272; }

/* ============ Moments ============ */
.moments { display: grid; grid-template-columns: repeat(3, 1fr); gap: clamp(20px, 3vw, 40px); padding-bottom: 140px; }
.moments li:nth-child(2) { transform: translateY(140px); }
.js .moments li:nth-child(2)[data-reveal] { transform: translateY(168px); }
.js .moments li:nth-child(2)[data-reveal].is-in { transform: translateY(140px); }
.js .moments li:nth-child(3)[data-reveal] { transition-delay: .12s; }
.moment-media { aspect-ratio: 4 / 5; overflow: hidden; }
.moment-media img { width: 100%; height: 100%; object-fit: cover; transition: transform 1.2s var(--ease); }
.moments li:hover .moment-media img { transform: scale(1.03); }
.moments .mono { margin-top: 22px; color: var(--ink-3); }
.moments h3 { margin-top: 6px; font-size: clamp(34px, 3.2vw, 48px); line-height: 1; }
.moments li > p:last-child { margin-top: 10px; max-width: 26em; color: var(--ink-2); }

/* ============ App (HTML phone mockups) ============ */
.app { background: var(--sand); margin-top: clamp(40px, 6vw, 100px); padding-bottom: clamp(110px, 13vw, 190px); }
.phones { display: flex; justify-content: center; align-items: flex-end; gap: clamp(20px, 3.4vw, 48px); }
.phone { flex: none; width: 250px; }
.phone-main { width: 284px; }
.screen {
  aspect-ratio: 9 / 19.2;
  overflow: hidden;
  border-radius: 40px;
  background: #fff;
  border: 9px solid #1b1814;
  box-shadow: 0 0 0 1px #3a342d, 0 50px 70px -40px rgba(60, 40, 20, .45);
  font-size: 10px;
  line-height: 1.5;
  color: #1b1814;
}
.phone-main .screen { font-size: 11px; }
.sb { display: flex; justify-content: space-between; align-items: center; padding: 11px 20px 6px; background: #f4f2ef; font-size: 1.1em; }
.sb i { width: 20px; height: 9px; border-radius: 3px; box-shadow: inset 0 0 0 1px #1b1814; position: relative; }
.sb i::after { content: ""; position: absolute; inset: 2px 5px 2px 2px; border-radius: 1px; background: #1b1814; }
.player { padding: 8px 12px 12px; background: #f4f2ef; border-radius: 0 0 20px 20px; }
.wf { height: 40px; display: flex; align-items: center; gap: 1.5px; padding: 0 8px; border-radius: 10px; background: #fff; }
.wf i { flex: 1; min-height: 3px; border-radius: 2px; background: #9b938a; }
.wf i:nth-child(n+34) { background: #1b1814; }
.times { display: flex; justify-content: space-between; margin: 5px 2px 6px; font-family: var(--mono); font-size: .75em; color: var(--ink-3); }
.ctrl { display: flex; justify-content: center; align-items: center; gap: 20px; }
.ctrl .skip { width: 16px; height: 16px; border-radius: 50%; box-shadow: inset 0 0 0 1.4px #1b1814; }
.ctrl .play { width: 28px; height: 28px; border-radius: 50%; background: #1b1814; position: relative; }
.ctrl .play::after { content: ""; position: absolute; left: 11px; top: 8px; border: 6px solid transparent; border-left: 8px solid #fff; border-right: 0; }
.tabs { display: flex; gap: 6px; padding: 10px 12px 8px; }
.tabs span { flex: 1; height: 24px; border-radius: 8px; background: #f0eeeb; }
.tabs .on { flex: 2.4; display: grid; place-items: center; background: #1b1814; color: #fff; font-weight: 600; font-size: .95em; }
.ts, .sum { padding: 4px 14px; }
.ts p { margin-bottom: 7px; }
.ts .who { margin-bottom: 1px; font-weight: 500; font-size: .85em; color: #c8793f; }
.ts .who.alt { color: #5b7fa3; }
.ts em { font-style: normal; margin-left: 4px; font-family: var(--mono); color: var(--ink-3); font-size: .9em; }
.sum h4 { font-size: 1.5em; line-height: 1.2; font-weight: 600; letter-spacing: -.01em; }
.sum .meta { margin: 4px 0 8px; font-family: var(--mono); font-size: .75em; color: var(--ink-3); }
.sum h5 { margin: 9px 0 3px; font-size: 1.05em; font-weight: 600; }
.sum ul { display: grid; gap: 2px; }
.sum li { position: relative; padding-left: 10px; }
.sum li::before { content: ""; position: absolute; left: 1px; top: .6em; width: 3px; height: 3px; border-radius: 50%; background: #1b1814; }
.sum .todo li::before { top: .38em; width: 6px; height: 6px; border-radius: 2px; background: none; box-shadow: inset 0 0 0 1px #9b938a; }
.map { display: block; width: 100%; padding: 6px 8px; }
.phone figcaption { margin-top: 20px; text-align: center; font-family: var(--mono); font-size: 12px; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-2); }
.solo { max-width: 540px; margin: 72px auto 0; text-align: center; font-size: 17px; color: var(--ink-2); }
.solo .mono { display: block; margin-bottom: 8px; color: var(--ink-3); }

/* ============ Details ============ */
.details { padding-bottom: clamp(110px, 13vw, 190px); }
.figures { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0 clamp(20px, 3vw, 40px); margin-bottom: clamp(72px, 9vw, 120px); }
.figures li { padding-top: 20px; border-top: 1px solid var(--ink); }
.figures b { display: block; font-size: clamp(64px, 7vw, 112px); line-height: .9; letter-spacing: -.03em; }
.figures small { margin-left: .08em; font-size: .36em; letter-spacing: 0; }
.figures span { display: block; margin-top: 14px; font-family: var(--mono); font-size: 12px; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); }
.spec { display: grid; grid-template-columns: 1fr 1fr; gap: 0 clamp(32px, 6vw, 96px); grid-auto-flow: column; grid-template-rows: repeat(8, auto); }
.spec > div { display: grid; grid-template-columns: 150px 1fr; gap: 16px; padding: 16px 0; border-bottom: 1px solid var(--line); }
.spec dt { padding-top: 3px; font-family: var(--mono); font-size: 12px; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); }
.spec dd { font-size: 16px; }

.more-link { display: inline-flex; gap: 8px; margin-top: 40px; font-weight: 500; border-bottom: 1px solid currentColor; padding-bottom: 2px; }
.more-link span { transition: transform .25s var(--ease); }
.more-link:hover span { transform: translateX(3px); }

/* ============ Download ============ */
.download { position: relative; overflow: hidden; height: 100svh; min-height: 680px; max-height: 1080px; text-align: center; }
.download-media { position: absolute; inset: 0; }
.download-media img { width: 100%; height: 100%; object-fit: cover; object-position: 50% 60%; transform: scale(var(--z, 1)); }
/* keep the headline area calm over the sunlit wall */
.download::after { content: ""; position: absolute; inset: 0 0 45%; background: linear-gradient(180deg, rgba(243, 238, 230, .55), rgba(243, 238, 230, 0)); pointer-events: none; }
.download-inner { position: relative; z-index: 1; max-width: var(--max); margin: 0 auto; padding: clamp(100px, 13vh, 150px) var(--gutter) 0; }
.download h2 { font-size: clamp(56px, 6.4vw, 104px); }
.download-actions { display: flex; justify-content: center; align-items: center; gap: 32px; margin-top: 40px; }
.qr { display: flex; align-items: center; gap: 14px; padding-left: 32px; border-left: 1px solid var(--line); text-align: left; font-size: 13px; line-height: 1.45; color: var(--ink-2); }
.qr img { width: 72px; height: 72px; padding: 6px; border-radius: 10px; background: #fff; }
.download-note { text-transform: none; }
.download .btn-ghost { background: rgba(243, 238, 230, .55); -webkit-backdrop-filter: blur(12px); backdrop-filter: blur(12px); }
.download-note { margin-top: 28px; color: var(--ink-2); }

/* ============ Footer ============ */
.footer-inner { max-width: var(--max); margin: 0 auto; padding: 40px var(--gutter) calc(40px + env(safe-area-inset-bottom)); display: grid; grid-template-columns: auto 1fr; gap: 24px 48px; font-size: 13px; color: var(--ink-3); }
.footer-inner .brand { color: var(--ink); }
.footer-inner .wordmark { font-size: 24px; }
.footer-links { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px 24px; align-self: center; }
.footer-links a:hover, .footer-meta a:hover { color: var(--ink); }
.footer-meta { grid-column: 1 / -1; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 6px 24px; padding-top: 22px; border-top: 1px solid var(--line); }

/* ============ Mobile dock ============ */
.dock { position: fixed; z-index: 40; left: 12px; right: 12px; bottom: calc(12px + env(safe-area-inset-bottom)); display: none; align-items: center; gap: 10px; padding: 8px 8px 8px 14px; border-radius: 99px; background: rgba(250, 247, 242, .86); -webkit-backdrop-filter: saturate(1.4) blur(20px); backdrop-filter: saturate(1.4) blur(20px); box-shadow: 0 0 0 1px var(--line), 0 16px 36px rgba(40, 30, 20, .16); transform: translateY(150%); transition: transform .45s var(--ease); }
.dock.is-visible { transform: none; }
.dock img { width: 24px; }
.dock .wordmark { font-size: 23px; }
.dock-btn { margin-left: auto; padding: 10px 18px; border-radius: 99px; background: var(--ink); color: var(--bg); font-size: 14px; font-weight: 500; }

/* ============ Reveal ============ */
.js [data-reveal] { opacity: 0; transform: translateY(28px); transition: opacity 1.1s var(--ease), transform 1.1s var(--ease); }
.js [data-reveal].is-in { opacity: 1; transform: none; }

/* ============ Chinese typography ============ */
/* Songti for display, Kaiti standing in for the italic; Latin and digits stay in Instrument Serif */
html:lang(zh) { --serif: "Instrument Serif", "Songti SC", "STSong", "Source Han Serif SC", "Noto Serif CJK SC", "Noto Serif SC", "SimSun", serif; }
html:lang(zh) body { line-height: 1.75; }
html:lang(zh) .serif { letter-spacing: .02em; line-height: 1.22; }
html:lang(zh) .serif em { font-family: "Instrument Serif", "Kaiti SC", "STKaiti", "KaiTi", "Songti SC", serif; font-style: normal; }
html:lang(zh) .hero h1 { font-size: clamp(50px, 5.4vw, 88px); line-height: 1.16; }
html:lang(zh) .manifesto p { font-size: clamp(30px, 3.8vw, 56px); line-height: 1.36; }
html:lang(zh) :is(.split-copy, .wide-copy) h3 { font-size: clamp(36px, 3.6vw, 58px); }
html:lang(zh) :is(.section-head h2, .how-copy h2, .download h2) { font-size: clamp(40px, 4.4vw, 70px); }
html:lang(zh) .moments h3 { font-size: clamp(30px, 2.6vw, 40px); }
html:lang(zh) .figures b { letter-spacing: -.03em; line-height: .9; }
html:lang(zh) :is(.label, .mono, .spec dt, .figures span) { letter-spacing: .1em; }
html:lang(zh) .t-line { grid-template-columns: 64px 52px 1fr; }

/* ============ Responsive ============ */
@media (max-width: 1080px) {
  .hero-copy { width: min(560px, 60vw); }
  .hero::after { background: linear-gradient(90deg, rgba(243, 238, 230, .92) 0%, rgba(243, 238, 230, .78) 40%, rgba(243, 238, 230, 0) 72%); }
  .how-sticky { grid-template-columns: 4fr 6fr; }
  .phone { width: 220px; }
  .phone-main { width: 250px; }
  .spec { grid-template-columns: 1fr; grid-auto-flow: row; grid-template-rows: none; }
  .figures { grid-template-columns: 1fr 1fr; gap: 40px 20px; }
}

@media (max-width: 760px) {
  body { font-size: 16px; }
  .nav { display: none; }
  .lang { margin-left: auto; }
  .header-inner { gap: 14px; }

  .hero { display: flex; flex-direction: column; height: auto; min-height: 0; max-height: none; padding-top: 100px; }
  .hero::after { display: none; }
  .hero-copy { position: static; order: -1; width: auto; padding: 0 var(--gutter) 40px; }
  .hero h1 { font-size: 60px; }
  .hero-lead { font-size: 16px; margin: 20px 0 28px; }
  .hero .cta-row { flex-direction: column; }
  .hero-media { position: relative; aspect-ratio: 4 / 5; }
  .hero-media img { object-position: 86% 50%; }

  .manifesto p { font-size: 34px; }

  .split, .split-night { grid-template-columns: 1fr; min-height: 0; }
  .split-media { min-height: 0; aspect-ratio: 4 / 5; }
  .split-copy { max-width: none; padding: 48px var(--gutter) 88px; justify-self: stretch; }
  .split-night .split-media { order: -1; }
  .split-copy h3, .wide-copy h3 { font-size: 46px; }
  .wide-media { aspect-ratio: 4 / 5; }
  .wide-media img { object-position: 36% 50%; }
  .wide-copy { grid-template-columns: 1fr; padding-top: 48px; }
  .wide-copy > p:last-child { margin: 24px 0 0; }

  .how { height: 380vh; }
  .how-sticky { grid-template-columns: 1fr; align-content: center; padding-top: 80px; padding-bottom: 96px; }
  .how-media { display: none; }
  .how-copy h2 { font-size: 46px; margin-bottom: 28px; }
  .sheet-body { height: 330px; }
  .t-line { grid-template-columns: 1fr; font-size: 15px; }
  .t-line b, .t-line .mono { display: inline; }
  .t-line .mono { padding: 0; }
  .steps { margin-top: 20px; font-size: 13px; }
  html:not(.js) .how-media { display: block; }

  .section-head h2, .download h2 { font-size: 46px; }
  .moments { grid-template-columns: 1fr; gap: 56px; padding-bottom: 0; }
  .moments li:nth-child(2), .js .moments li:nth-child(2)[data-reveal].is-in { transform: none; }
  .js .moments li:nth-child(2)[data-reveal] { transform: translateY(28px); }
  .moments h3 { font-size: 36px; }

  .phones { justify-content: flex-start; overflow-x: auto; scroll-snap-type: x mandatory; margin: 0 calc(-1 * var(--gutter)); padding: 0 var(--gutter) 24px; scrollbar-width: none; }
  .phones::-webkit-scrollbar { display: none; }
  .phone, .phone-main { width: 240px; scroll-snap-align: center; }
  .phone-main { order: -1; }
  .solo { margin-top: 36px; text-align: left; }

  .spec > div { grid-template-columns: 1fr; gap: 4px; }
  .figures b { font-size: 64px; }

  .download { height: auto; min-height: 0; max-height: none; display: flex; flex-direction: column; text-align: left; }
  .download::after { display: none; }
  .download-media { position: relative; order: 2; aspect-ratio: 4 / 5; }
  .download-media img { object-position: 58% 50%; }
  .download-inner { padding: 96px var(--gutter) 48px; width: 100%; }
  .download-actions { flex-direction: column; align-items: stretch; gap: 0; }
  .download .cta-row { flex-direction: column; }
  .qr { display: none; }
  .footer-inner { grid-template-columns: 1fr; }
  .footer-links { justify-content: flex-start; }
  .site-footer { padding-bottom: 80px; }
  .dock { display: flex; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; scroll-behavior: auto !important; }
  .js [data-reveal] { opacity: 1; transform: none; }
}

/* ============ In-app browser guide (WeChat, DingTalk, Weibo…) ============ */
/* No card: one sentence set like a caption on the dimmed page, an arrow drawn up to the host app's ··· menu */
.inapp-open, .inapp-open body { overflow: hidden; }
.inapp { position: fixed; z-index: 100; inset: 0; display: flex; flex-direction: column; padding: calc(150px + env(safe-area-inset-top)) 28px calc(22px + env(safe-area-inset-bottom)); color: var(--on-night); background: radial-gradient(120% 70% at 85% 0%, rgba(19, 17, 14, .7), rgba(19, 17, 14, .9) 60%); -webkit-backdrop-filter: blur(14px) saturate(1.1); backdrop-filter: blur(14px) saturate(1.1); opacity: 0; transition: opacity .4s ease; }
.inapp.is-in { opacity: 1; }

.inapp-photo { position: absolute; z-index: -1; left: 0; right: 0; bottom: 0; height: 58%; overflow: hidden; opacity: 0; transition: opacity 1.4s ease; -webkit-mask-image: linear-gradient(to top, #000 25%, transparent); mask-image: linear-gradient(to top, #000 25%, transparent); }
.inapp-photo img { width: 100%; height: 100%; object-fit: cover; object-position: 60% 40%; transform: scale(1.1); transition: transform 7s cubic-bezier(.16, .6, .2, 1); }
.inapp.is-in .inapp-photo.is-loaded { opacity: .42; }
.inapp.is-in .inapp-photo.is-loaded img { transform: none; }
.inapp { isolation: isolate; }
.inapp-mark { position: absolute; top: calc(20px + env(safe-area-inset-top)); left: 28px; font-size: 22px; opacity: .55; }

.inapp-pointer { position: absolute; top: calc(4px + env(safe-area-inset-top)); right: 14px; width: 112px; height: 140px; pointer-events: none; }
.inapp-pointer svg { position: absolute; inset: 0; width: 100%; height: 100%; overflow: visible; clip-path: inset(100% 0 0 0); transition: clip-path 1s .35s var(--ease); }
.inapp.is-in .inapp-pointer svg { clip-path: inset(0 0 0 0); }
.inapp-pointer path { stroke: currentColor; stroke-width: 1.4; stroke-linecap: round; stroke-linejoin: round; }
.inapp-curve { stroke-dasharray: 2 6; }
.inapp-head { stroke-width: 1.8; }
.inapp-ping { position: absolute; top: -9px; right: -9px; width: 30px; height: 30px; }
.inapp-ping::before { content: ""; position: absolute; inset: 0; border-radius: 50%; box-shadow: inset 0 0 0 1px var(--on-night); animation: inappPing 2s var(--ease) infinite; }
.inapp-ping::after { content: ""; position: absolute; left: 50%; top: 50%; width: 6px; height: 6px; margin: -3px 0 0 -3px; border-radius: 50%; background: var(--on-night); }
@keyframes inappPing { 0% { transform: scale(.5); opacity: 1; } 80%, 100% { transform: scale(1.7); opacity: 0; } }

.inapp-body { flex: 1; max-width: 420px; }
.inapp-body > * { opacity: 0; transform: translateY(14px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.inapp.is-in .inapp-body > * { opacity: 1; transform: none; }
.inapp.is-in .inapp-body > :nth-child(2) { transition-delay: .08s; }
.inapp.is-in .inapp-body > :nth-child(3) { transition-delay: .16s; }
.inapp-eyebrow { font-size: 14px; color: var(--on-night-2); }
.inapp h2 { margin-top: 14px; font-size: 44px; line-height: 1.04; letter-spacing: -.02em; }
.inapp h2 em { color: #e3cfa9; }
.inapp-dots { display: inline-flex; align-items: center; gap: .1em; height: .8em; padding: 0 .26em; border-radius: 99px; box-shadow: inset 0 0 0 1px rgba(239, 231, 218, .5); vertical-align: .02em; }
.inapp-dots { animation: inappEcho 2s var(--ease) infinite; }
@keyframes inappEcho { 0%, 100% { box-shadow: inset 0 0 0 1px rgba(239, 231, 218, .5), 0 0 0 0 rgba(239, 231, 218, .28); } 60% { box-shadow: inset 0 0 0 1px rgba(239, 231, 218, .5), 0 0 0 7px rgba(239, 231, 218, 0); } }
.inapp-dots i { width: .12em; height: .12em; border-radius: 50%; background: currentColor; }
.inapp-note { margin-top: 22px; font-size: 14px; line-height: 1.7; color: var(--on-night-2); }

.inapp-foot { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding-top: 18px; border-top: 1px solid rgba(239, 231, 218, .14); }
.inapp-copy { padding: 8px 0; border: 0; background: none; color: var(--on-night); font: inherit; font-size: 14px; text-decoration: underline; text-decoration-color: rgba(239, 231, 218, .4); text-underline-offset: 5px; cursor: pointer; }
.inapp-copy.is-done { text-decoration: none; color: #e3cfa9; }
.inapp-close { display: grid; place-items: center; width: 40px; height: 40px; margin-right: -8px; border: 0; border-radius: 50%; background: none; color: var(--on-night); cursor: pointer; }
.inapp-close svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.4; stroke-linecap: round; }

html:lang(zh) .inapp h2 { font-size: 36px; line-height: 1.42; letter-spacing: .02em; }
html:lang(zh) .inapp-dots { vertical-align: .08em; }
@media (max-height: 640px) {
  .inapp { padding-top: calc(118px + env(safe-area-inset-top)); }
  .inapp-pointer { height: 112px; }
  .inapp h2 { font-size: 38px; }
  html:lang(zh) .inapp h2 { font-size: 31px; }
}