/* =========================================================================
   Stoker — landing page styles
   Design language: "Forge / Tended Ember". Ember is the single accent.
   Adaptive light/dark (follows system; overridable via [data-theme]).
   ========================================================================= */

/* ---------- Tokens ---------- */
:root {
  --ember: #E36E43;
  --ember-ink: #C75A33;        /* ember pressed deeper for small marks on light */
  --ember-btn: #B44E2A;        /* ember pressed deeper so white text clears WCAG AA (5.17:1) */
  --spark: #FFB347;
  --series-claude: #7B5FCB;
  --series-codex: #1A8F58;

  --bg: #FAF8F6;
  --bg-2: #F2EDE6;             /* slightly deeper band */
  --surface: #FFFFFF;
  --elevated: rgba(20, 16, 12, 0.022);
  --hairline: rgba(20, 16, 12, 0.10);
  --hairline-strong: rgba(20, 16, 12, 0.16);

  --text-1: rgba(20, 16, 12, 0.92);
  --text-2: rgba(20, 16, 12, 0.62);
  --text-3: rgba(20, 16, 12, 0.62);  /* lifted from .42 → AA on warm-white (≈5.2:1) */
  --on-ember: #fff;

  --glow-ember: rgba(227, 110, 67, 0.16);
  --glow-spark: rgba(255, 179, 71, 0.10);
  --hero-bg: #1B1410;          /* hero is always a warm near-black stage */
  --hero-text-1: rgba(255, 251, 247, 0.96);
  --hero-text-2: rgba(255, 248, 242, 0.66);
  --hero-hairline: rgba(255, 240, 230, 0.14);

  --radius-sm: 9px;
  --radius-md: 15px;
  --radius-lg: 22px;
  --radius-xl: 30px;

  --maxw: 1120px;
  --maxw-narrow: 760px;
  --pad-x: clamp(20px, 5vw, 40px);

  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", system-ui, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-mono: ui-monospace, "SF Mono", "JetBrains Mono", "Menlo", monospace;

  --ease-out: cubic-bezier(.16, 1, .3, 1);
  --dur-fast: .22s;
  --dur: .5s;
  --stagger: 70ms;

  --nav-h: 62px;
  color-scheme: light;
}

/* Dark — follow system unless explicitly forced light */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --ember-ink: #E36E43;
    --bg: #15110D;
    --bg-2: #1C1712;
    --surface: #1E1813;
    --elevated: rgba(255, 248, 240, 0.035);
    --hairline: rgba(255, 244, 235, 0.10);
    --hairline-strong: rgba(255, 244, 235, 0.18);
    --text-1: rgba(255, 250, 245, 0.93);
    --text-2: rgba(255, 248, 242, 0.64);
    --text-3: rgba(255, 246, 238, 0.54);  /* lifted from .42 → AA on dark (≈5.2:1) */
    --glow-ember: rgba(227, 110, 67, 0.24);
    --glow-spark: rgba(255, 179, 71, 0.12);
    --hero-bg: #120D0A;
    --series-claude: #8F70D9;
    --series-codex: #2EBF7D;
    color-scheme: dark;
  }
}
/* Explicit override */
[data-theme="dark"] {
  --ember-ink: #E36E43;
  --bg: #15110D; --bg-2: #1C1712; --surface: #1E1813;
  --elevated: rgba(255, 248, 240, 0.035);
  --hairline: rgba(255, 244, 235, 0.10); --hairline-strong: rgba(255, 244, 235, 0.18);
  --text-1: rgba(255, 250, 245, 0.93); --text-2: rgba(255, 248, 242, 0.64); --text-3: rgba(255, 246, 238, 0.54);
  --glow-ember: rgba(227, 110, 67, 0.24); --glow-spark: rgba(255, 179, 71, 0.12);
  --hero-bg: #120D0A; --series-claude: #8F70D9; --series-codex: #2EBF7D;
  color-scheme: dark;
}

/* ---------- Reset / base ---------- */
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text-1);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
h1, h2, h3, h4 { margin: 0; font-weight: 600; line-height: 1.2; letter-spacing: -0.01em; }
p { margin: 0; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
svg { display: block; }
.mono { font-family: var(--font-mono); }
:focus-visible { outline: 2px solid var(--ember); outline-offset: 3px; border-radius: 6px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

.skip-link {
  position: fixed; top: 10px; left: 50%; transform: translateX(-50%) translateY(-160%);
  background: var(--ember); color: var(--on-ember); padding: 10px 18px; border-radius: 999px;
  z-index: 200; font-size: 14px; font-weight: 600; transition: transform var(--dur-fast) var(--ease-out);
}
.skip-link:focus { transform: translateX(-50%) translateY(0); }

.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--pad-x); }
.container--narrow { max-width: var(--maxw-narrow); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-weight: 600; font-size: 15px; line-height: 1; white-space: nowrap;
  padding: 12px 20px; border-radius: 999px; border: 1px solid transparent;
  cursor: pointer; transition: transform var(--dur-fast) var(--ease-out),
    background var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out),
    box-shadow var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out);
}
.btn--lg { padding: 15px 26px; font-size: 16px; }
.btn--primary {
  background: var(--ember-btn); color: var(--on-ember);
  box-shadow: 0 1px 2px rgba(0,0,0,.16), 0 8px 26px var(--glow-ember);
}
.btn--primary:hover { background: #ec7a50; box-shadow: 0 2px 6px rgba(0,0,0,.2), 0 12px 36px var(--glow-ember); }
.btn--primary:active { transform: translateY(1px) scale(.99); }
.btn--ghost { background: var(--elevated); color: var(--text-1); border-color: var(--hairline-strong); }
.btn--ghost:hover { border-color: var(--ember); color: var(--ember-ink); }

/* ---------- Nav ---------- */
.nav {
  position: fixed; inset: 0 0 auto 0; z-index: 100; height: var(--nav-h);
  display: flex; align-items: center;
  transition: background var(--dur) var(--ease-out), border-color var(--dur) var(--ease-out), backdrop-filter var(--dur) var(--ease-out);
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: color-mix(in srgb, var(--bg) 72%, transparent);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  backdrop-filter: blur(14px) saturate(140%);
  border-bottom-color: var(--hairline);
}
/* The transparent nav overlays the ALWAYS-dark hero, but its text colors follow the
   page theme — so in light mode the dark nav text vanishes on the dark hero. While the
   nav is unscrolled (over the hero) force hero-light text; once .scrolled it gets a
   solid themed background and reverts to the normal themed text colors. */
.nav:not(.scrolled) .brand,
.nav:not(.scrolled) .brand__mark,
.nav:not(.scrolled) .brand__name { color: var(--hero-text-1); }
.nav:not(.scrolled) .nav__links a,
.nav:not(.scrolled) .icon-btn,
.nav:not(.scrolled) .lang-toggle { color: var(--hero-text-2); }
.nav:not(.scrolled) .nav__links a:hover,
.nav:not(.scrolled) .icon-btn:hover { color: var(--hero-text-1); }
.nav:not(.scrolled) .lang-toggle { border-color: var(--hero-hairline); }
.nav:not(.scrolled) .icon-btn:hover { background: rgba(255, 255, 255, .08); border-color: var(--hero-hairline); }
html[lang="en"] .nav:not(.scrolled) [data-lang-en],
html[lang="zh"] .nav:not(.scrolled) [data-lang-zh] { color: var(--ember); }
.nav__inner { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--pad-x);
  display: flex; align-items: center; gap: 18px; }
.brand { display: inline-flex; align-items: center; gap: 9px; color: var(--text-1); }
.brand__mark { display: inline-flex; color: var(--text-1); }
.brand__name { font-weight: 650; font-size: 18px; letter-spacing: -0.02em; }
.nav__links { display: flex; gap: 26px; margin-left: 12px; }
.nav__links a { color: var(--text-2); font-size: 15px; transition: color var(--dur-fast); position: relative; }
.nav__links a:hover { color: var(--text-1); }
.nav__actions { display: flex; align-items: center; gap: 8px; margin-left: auto; }

.lang-toggle {
  display: inline-flex; align-items: center; gap: 5px; background: none; border: 1px solid var(--hairline-strong);
  color: var(--text-3); border-radius: 999px; padding: 6px 11px; font-size: 13px; font-weight: 600; cursor: pointer;
  font-family: inherit; transition: border-color var(--dur-fast), color var(--dur-fast);
}
.lang-toggle .sep { opacity: .5; }
.lang-toggle:hover { border-color: var(--ember); }
html[lang="en"] [data-lang-en], html[lang="zh"] [data-lang-zh] { color: var(--ember-ink); }
.lang-toggle--sm { padding: 5px 10px; font-size: 12px; }

.icon-btn {
  display: inline-flex; align-items: center; justify-content: center; width: 36px; height: 36px;
  border-radius: 999px; border: 1px solid transparent; color: var(--text-2); background: none; cursor: pointer;
  transition: background var(--dur-fast), color var(--dur-fast), border-color var(--dur-fast);
}
.icon-btn:hover { color: var(--text-1); background: var(--elevated); border-color: var(--hairline); }
/* Theme toggle icon: show what you'd switch TO is avoided — show current mode.
   Default (auto): sun in light system, moon in dark system. Explicit data-theme wins. */
.i-sun { display: block; }
.i-moon { display: none; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .i-sun { display: none; }
  :root:not([data-theme="light"]) .i-moon { display: block; }
}
[data-theme="light"] .i-sun { display: block; }
[data-theme="light"] .i-moon { display: none; }
[data-theme="dark"] .i-sun { display: none; }
[data-theme="dark"] .i-moon { display: block; }
.nav__cta { padding: 9px 18px; font-size: 14px; }

@media (max-width: 860px) {
  .nav__links { display: none; }
  .brand__name { font-size: 17px; }
}
@media (max-width: 520px) {
  .nav__cta, .icon-btn[aria-label="GitHub repository"] { display: none; }
}

/* ---------- Hero ---------- */
.hero {
  position: relative; isolation: isolate; overflow: hidden;
  background: var(--hero-bg); color: var(--hero-text-1);
  padding-top: calc(var(--nav-h) + clamp(48px, 9vw, 104px));
  padding-bottom: clamp(20px, 6vw, 60px);
  border-bottom: 1px solid var(--hero-hairline);
}
.hero__bg { position: absolute; inset: 0; z-index: -1; }
.hero__glow {
  position: absolute; inset: 0;
  background:
    radial-gradient(58% 50% at 50% 72%, var(--glow-ember), transparent 70%),
    radial-gradient(30% 32% at 72% 26%, var(--glow-spark), transparent 72%),
    linear-gradient(to bottom, rgba(0,0,0,.45), transparent 30%);
  animation: breathe 18s var(--ease-out) infinite;
}
@keyframes breathe { 0%,100% { transform: scale(1); opacity: .92; } 50% { transform: scale(1.04); opacity: 1; } }
.hero__sparks { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; }
.hero__noise {
  position: absolute; inset: 0; pointer-events: none; opacity: .04; mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}
.hero__inner { max-width: 880px; margin-inline: auto; padding-inline: var(--pad-x); text-align: center; }

.eyebrow {
  display: inline-flex; align-items: center; gap: 8px; margin: 0 auto 22px;
  padding: 6px 14px 6px 11px; border-radius: 999px; font-size: 13px; font-weight: 600; letter-spacing: .01em;
  color: var(--hero-text-2); background: rgba(255,255,255,.05); border: 1px solid var(--hero-hairline);
}
.eyebrow__dot { width: 7px; height: 7px; border-radius: 50%; background: var(--ember);
  box-shadow: 0 0 0 0 var(--ember); animation: pulse-dot 3.4s ease-out infinite; }
@keyframes pulse-dot { 0% { box-shadow: 0 0 0 0 rgba(227,110,67,.5); } 70%,100% { box-shadow: 0 0 0 9px rgba(227,110,67,0); } }

.hero__title {
  font-size: clamp(2.4rem, 5.4vw + 1rem, 4.6rem); font-weight: 680; letter-spacing: -0.03em;
  line-height: 1.04; margin: 0 auto; max-width: 16ch; color: var(--hero-text-1);
}
.hero__sub { margin: 22px auto 0; max-width: 56ch; font-size: clamp(1rem, 1.4vw + .6rem, 1.22rem); color: var(--hero-text-2); }
.hero__cta { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 30px; }
.hero__cta .btn--ghost { background: rgba(255,255,255,.06); border-color: var(--hero-hairline); color: var(--hero-text-1); }
.hero__cta .btn--ghost:hover { border-color: var(--ember); color: #fff; }
.hero__meta { margin-top: 18px; font-size: 13.5px; color: var(--hero-text-2); letter-spacing: .01em; }

/* schedule marquee */
.schedule { margin: 38px auto 0; max-width: 460px; display: flex; align-items: center; gap: 14px; }
.schedule__label { font-size: 11px; text-transform: uppercase; letter-spacing: .12em; color: var(--hero-text-2); white-space: nowrap; }
.schedule__track { position: relative; flex: 1; overflow: hidden;
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 18%, #000 82%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 18%, #000 82%, transparent); }
.schedule__marquee { display: inline-flex; gap: 14px; white-space: nowrap; font-family: var(--font-mono);
  font-size: 14px; color: var(--hero-text-1); animation: marquee 26s linear infinite; }
.schedule__marquee i { color: var(--ember); font-style: normal; }
.schedule__track:hover .schedule__marquee { animation-play-state: paused; }
@keyframes marquee { from { transform: translateX(0); } to { transform: translateX(-50%); } }

/* hero product window */
.hero__shot { margin: clamp(40px, 7vw, 72px) auto 0; max-width: 560px; perspective: 1600px; }
.window {
  border-radius: var(--radius-lg); overflow: hidden; background: var(--surface);
  border: 1px solid var(--hairline);
  box-shadow: 0 1px 0 rgba(255,255,255,.06) inset, 0 18px 40px rgba(0,0,0,.28), 0 40px 90px rgba(227,110,67,.10);
}
.window--hero { transform: rotateX(1.5deg) rotateY(-2deg); transition: transform var(--dur) var(--ease-out); }
.window--hero:hover { transform: rotateX(0) rotateY(0); }
.window__bar { display: flex; align-items: center; gap: 7px; padding: 11px 14px;
  background: color-mix(in srgb, var(--surface) 86%, var(--text-1)); border-bottom: 1px solid var(--hairline); }
.dot { width: 11px; height: 11px; border-radius: 50%; background: var(--hairline-strong); }
.dot--r { background: #FF5F57; } .dot--y { background: #FEBC2E; } .dot--g { background: #28C840; }
.window__img { width: 100%; height: auto; display: block; background: var(--bg-2); }

/* ---------- Sections ---------- */
.section { padding-block: clamp(64px, 10vw, 120px); }
.section__title { font-size: clamp(1.7rem, 2.6vw + .6rem, 2.7rem); max-width: 20ch; letter-spacing: -0.02em; }
.problem .section__title, .cost .section__title, .download .section__title, .faq .section__title, .shots .section__title, .features .section__title, .how .section__title { margin-inline: auto; text-align: center; }
.section__sub { margin: 16px auto 0; max-width: 60ch; text-align: center; color: var(--text-2); font-size: clamp(1rem, 1vw + .6rem, 1.12rem); }
.section .grid, .section .bento, .section .steps, .section .cost__rows, .section .tabs,
.section .shots__frame, .section .trust__badges, .section .faq__list, .section .download__cards { margin-top: clamp(36px, 5vw, 56px); }

.grid { display: grid; gap: 18px; }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid > *, .bento__cell, .step, .card, .dlcard, .terminal, .window { min-width: 0; }

/* card */
.card { background: var(--elevated); border-radius: var(--radius-md); padding: 24px;
  box-shadow: 0 0 0 1px var(--hairline); transition: box-shadow var(--dur-fast) var(--ease-out), transform var(--dur-fast) var(--ease-out); }
.card__t { font-size: 1.06rem; }
.card__d { margin-top: 8px; color: var(--text-2); font-size: 15px; }

/* ---------- How / steps ---------- */
.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; counter-reset: s; position: relative; }
.step { position: relative; padding: 26px 20px; border-radius: var(--radius-md); background: var(--elevated); box-shadow: 0 0 0 1px var(--hairline); }
.step__n { display: inline-flex; align-items: center; justify-content: center; width: 38px; height: 38px; border-radius: 50%;
  font-weight: 650; font-size: 16px; color: var(--ember-ink); border: 1.5px solid var(--ember); margin-bottom: 14px;
  background: color-mix(in srgb, var(--ember) 9%, transparent); }
.step__t { font-size: 1.04rem; }
.step__d { margin-top: 8px; color: var(--text-2); font-size: 14.5px; }

.terminal { margin: clamp(34px, 5vw, 52px) auto 0; max-width: 700px; border-radius: var(--radius-md); overflow: hidden;
  background: #161210; box-shadow: 0 0 0 1px var(--hairline), 0 22px 50px rgba(0,0,0,.28); }
.terminal__bar { display: flex; align-items: center; gap: 7px; padding: 11px 14px; background: #1f1916; border-bottom: 1px solid rgba(255,255,255,.06); }
.terminal__title { margin-left: 8px; font-size: 12px; color: rgba(255,248,242,.5); font-family: var(--font-mono); }
.terminal__body { margin: 0; padding: 18px 20px; overflow-x: auto; font-family: var(--font-mono); font-size: 13.5px; line-height: 1.85; color: rgba(255,250,245,.92); }
.terminal__body code { white-space: pre; }
.c-pmt { color: var(--ember); user-select: none; margin-right: 8px; }
.c-com { color: rgba(255,248,242,.4); }
.c-ok { color: #5fd08a; }

/* ---------- Features bento ---------- */
.bento { display: grid; grid-template-columns: repeat(6, 1fr); gap: 18px; }
.bento__cell { grid-column: span 2; background: var(--elevated); border-radius: var(--radius-md); padding: 26px;
  box-shadow: 0 0 0 1px var(--hairline); position: relative; overflow: hidden;
  transition: transform var(--dur-fast) var(--ease-out), box-shadow var(--dur-fast) var(--ease-out); }
.bento__cell--wide { grid-column: span 3; }
.bento__cell::before { content: ""; position: absolute; inset: 0; opacity: 0; transition: opacity var(--dur-fast);
  background: radial-gradient(220px circle at var(--mx, 50%) var(--my, 0%), rgba(227,110,67,.12), transparent 70%); }
@media (hover: hover) {
  .bento__cell:hover { transform: translateY(-3px); box-shadow: 0 0 0 1px var(--hairline-strong), 0 16px 36px rgba(0,0,0,.14); }
  .bento__cell:hover::before { opacity: 1; }
  .card:hover { transform: translateY(-2px); box-shadow: 0 0 0 1px var(--hairline-strong), 0 14px 30px rgba(0,0,0,.12); }
}
.ficon { position: relative; display: inline-flex; align-items: center; justify-content: center; width: 50px; height: 50px;
  border-radius: 13px; color: var(--text-1); background: color-mix(in srgb, var(--ember) 8%, var(--elevated));
  box-shadow: 0 0 0 1px var(--hairline); margin-bottom: 18px; }
.ficon__dot { position: absolute; top: 11px; right: 11px; width: 6px; height: 6px; border-radius: 50%; background: var(--ember); }
.bento__t { font-size: 1.1rem; }
.bento__d { margin-top: 8px; color: var(--text-2); font-size: 15px; position: relative; }

/* ---------- Cost ---------- */
.cost__rows { display: grid; gap: 12px; }
.cost__row { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  padding: 18px 22px; border-radius: var(--radius-md); background: var(--elevated); box-shadow: 0 0 0 1px var(--hairline); }
.cost__tool { display: inline-flex; align-items: center; gap: 10px; font-weight: 600; font-size: 1.02rem; }
.cost__tool b { width: 9px; height: 9px; border-radius: 50%; background: var(--series, var(--ember)); }
.cost__val { color: var(--text-2); font-size: 14.5px; }
.cost__month { margin-top: 22px; text-align: center; font-size: 1.06rem; color: var(--text-1); }
.cost__month::before { content: ""; }
.disclose { margin: 18px auto 0; max-width: 60ch; text-align: center; }
.disclose summary { cursor: pointer; color: var(--text-3); font-size: 14px; list-style: none; }
.disclose summary::-webkit-details-marker { display: none; }
.disclose[open] summary { color: var(--text-2); }

/* ---------- Screenshots ---------- */
.tabs { display: inline-flex; gap: 4px; padding: 4px; border-radius: 999px; background: var(--elevated);
  box-shadow: 0 0 0 1px var(--hairline); margin-inline: auto; }
.shots .tabs { display: flex; width: fit-content; }
.tab { border: none; background: none; cursor: pointer; font-family: inherit; font-size: 14px; font-weight: 600;
  color: var(--text-2); padding: 8px 20px; border-radius: 999px; transition: color var(--dur-fast), background var(--dur-fast); }
.tab.is-active { color: var(--on-ember); background: var(--ember); }
.shots__frame { max-width: 620px; margin-inline: auto; }
/* cross-fade applies to any product window when its screenshot src swaps (lang/theme/tab) */
.window__img { transition: opacity var(--dur) var(--ease-out); }
.window.is-swapping .window__img { opacity: 0; }

/* ---------- Trust ---------- */
.trust__badges { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; }
.badge { display: inline-flex; align-items: center; gap: 8px; padding: 9px 16px; border-radius: 999px;
  font-size: 14px; font-weight: 600; color: var(--text-2); background: var(--elevated); box-shadow: 0 0 0 1px var(--hairline); }
.badge svg { color: var(--ember-ink); }
.trust__note { margin: 22px auto 0; max-width: 64ch; text-align: center; color: var(--text-3); font-size: 13.5px; line-height: 1.7; }

/* ---------- FAQ ---------- */
.faq__list { max-width: 720px; margin-inline: auto; border-radius: var(--radius-md); overflow: hidden; box-shadow: 0 0 0 1px var(--hairline); }
.qa { background: var(--elevated); border-bottom: 1px solid var(--hairline); }
.qa:last-child { border-bottom: none; }
.qa summary { cursor: pointer; list-style: none; padding: 20px 54px 20px 22px; font-weight: 600; font-size: 1.02rem; position: relative; color: var(--text-1); }
.qa summary::-webkit-details-marker { display: none; }
.qa summary::after { content: ""; position: absolute; right: 24px; top: 50%; width: 9px; height: 9px;
  border-right: 2px solid var(--text-3); border-bottom: 2px solid var(--text-3); transform: translateY(-65%) rotate(45deg);
  transition: transform var(--dur-fast) var(--ease-out); }
.qa[open] summary::after { transform: translateY(-35%) rotate(225deg); border-color: var(--ember); }
.qa p { padding: 0 54px 22px 22px; margin: 0; color: var(--text-2); font-size: 15px; }

/* ---------- Download ---------- */
.download { position: relative; overflow: hidden; background: var(--bg-2); }
.download__glow { position: absolute; inset: 0; pointer-events: none;
  background: radial-gradient(50% 60% at 50% 110%, var(--glow-ember), transparent 70%); }
.download__cards { align-items: stretch; }
.dlcard { display: flex; flex-direction: column; gap: 14px; padding: 28px; border-radius: var(--radius-lg);
  background: var(--surface); box-shadow: 0 0 0 1px var(--hairline); }
.dlcard--feature { box-shadow: 0 0 0 1.5px var(--ember), 0 20px 50px var(--glow-ember); }
.dlcard__tag { font-weight: 650; font-size: 1.12rem; }
.dlcard--feature .dlcard__tag { color: var(--ember-ink); }
.dlcard__d { color: var(--text-2); font-size: 15px; }
.dlcard .btn { align-self: flex-start; }
.dlcard__note { color: var(--text-3); font-size: 13px; line-height: 1.6; margin-top: auto; }
.dlcard__code { margin: 0; padding: 16px; border-radius: var(--radius-sm); background: #161210; color: rgba(255,250,245,.9);
  font-size: 13px; line-height: 1.7; overflow-x: auto; }
.download__outro { margin: clamp(36px,5vw,52px) auto 0; text-align: center; font-size: clamp(1.3rem, 2vw + .6rem, 1.9rem);
  font-weight: 650; letter-spacing: -0.02em; color: var(--ember-ink); }

/* ---------- Footer ---------- */
.footer {
  border-top: 1px solid var(--hairline);
  padding-block: clamp(56px, 7vw, 84px) 32px;
  background: var(--bg);
}
.footer__top {
  display: grid;
  grid-template-columns: minmax(240px, 1fr) minmax(520px, 1.65fr);
  align-items: start;
  gap: clamp(48px, 8vw, 104px);
}
.footer__brand {
  display: grid;
  justify-items: start;
  max-width: 320px;
}
.footer__brand .brand { justify-content: flex-start; }
.footer__brand .brand__name { font-size: 18px; }
.footer__tagline {
  margin-top: 14px;
  max-width: 30ch;
  color: var(--text-2);
  font-size: 14.5px;
  line-height: 1.7;
}
.footer__cols {
  width: 100%;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(28px, 4.5vw, 60px);
}
.footer__col {
  min-width: 0;
  display: grid;
  justify-items: start;
  align-content: start;
  gap: 10px;
}
.footer__col h4 {
  margin: 0 0 2px;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .13em;
  color: var(--text-3);
  font-weight: 650;
}
.footer__col a {
  color: var(--text-2);
  font-size: 14.5px;
  line-height: 1.35;
  text-align: left;
  transition: color var(--dur-fast);
}
.footer__col a:hover { color: var(--ember-ink); }
.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  margin-top: clamp(42px, 6vw, 64px);
  padding-top: 24px;
  border-top: 1px solid var(--hairline);
}
.footer__legal {
  color: var(--text-3);
  font-size: 13px;
  line-height: 1.6;
  text-align: left;
}
.footer__actions {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}
.footer__social {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  color: var(--text-3);
  border: 1px solid var(--hairline-strong);
  border-radius: 999px;
  transition: color var(--dur-fast), border-color var(--dur-fast), background var(--dur-fast);
}
.footer__social:hover {
  color: var(--text-1);
  border-color: var(--ember);
  background: var(--elevated);
}

/* ---------- Reveal animation (progressive enhancement) ----------
   Default: fully visible. Only when JS confirms IntersectionObserver + motion-OK
   (html.js-reveal, set by the head bootstrap) do we hide-then-reveal on scroll.
   No JS / no IO / reduced-motion → content never hidden. */
.reveal { opacity: 1; transform: none; }
html.js-reveal .reveal {
  opacity: 0; transform: translateY(18px);
  transition: opacity var(--dur) var(--ease-out), transform var(--dur) var(--ease-out);
  transition-delay: calc(var(--i, 0) * var(--stagger)); will-change: opacity, transform;
}
html.js-reveal .reveal.is-in { opacity: 1; transform: none; }

/* ---------- Language visibility ---------- */
html[lang="en"] [data-lang-only="zh"], html[lang="zh"] [data-lang-only="en"] { display: none; }

/* ---------- Chinese typography tuning ---------- */
html[lang="zh"] .hero__title { letter-spacing: 0; font-weight: 640; line-height: 1.18; }
html[lang="zh"] .section__title { letter-spacing: 0; line-height: 1.3; }
html[lang="zh"] .download__outro { letter-spacing: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 920px) {
  .bento { grid-template-columns: repeat(4, 1fr); }
  .bento__cell, .bento__cell--wide { grid-column: span 2; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .footer__top {
    grid-template-columns: 1fr;
    gap: 34px;
  }
  .footer__brand {
    max-width: 420px;
  }
  .footer__cols {
    max-width: 720px;
  }
}
@media (max-width: 680px) {
  .grid--3, .grid--2 { grid-template-columns: 1fr; }
  .bento { grid-template-columns: 1fr; }
  .bento__cell, .bento__cell--wide { grid-column: span 1; }
  .steps { grid-template-columns: 1fr; }
  .footer__cols {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px 36px;
  }
  .footer__bottom {
    align-items: flex-start;
    flex-direction: column;
  }
  .window--hero { transform: none; }
}
@media (max-width: 520px) {
  :root {
    --nav-h: 58px;
    --pad-x: 18px;
  }
  .nav__inner { gap: 12px; }
  .brand__name { font-size: 16px; }
  .hero {
    padding-top: calc(var(--nav-h) + 24px);
    padding-bottom: 16px;
  }
  .hero__inner { max-width: 390px; }
  .eyebrow {
    margin-bottom: 14px;
    padding: 5px 12px 5px 10px;
    font-size: 12px;
  }
  .hero__title {
    max-width: 14ch;
    font-size: clamp(2.02rem, 8.5vw + .25rem, 2.35rem);
    line-height: 1.07;
  }
  .hero__sub {
    margin-top: 14px;
    max-width: 33ch;
    font-size: .98rem;
    line-height: 1.52;
  }
  .hero__cta {
    flex-wrap: nowrap;
    gap: 9px;
    margin-top: 20px;
  }
  .hero__cta .btn--lg {
    flex: 1 1 0;
    min-width: 0;
    padding: 13px 10px;
    font-size: 14px;
  }
  .hero__meta {
    display: none;
  }
  .hero__shot {
    max-width: min(74vw, 280px);
    margin-top: 20px;
  }
  .hero .schedule { display: none; }
  .window { border-radius: 18px; }
  .section { padding-block: 56px; }
  .problem { padding-top: 16px; }
  html.js-reveal .problem .section__title.reveal {
    opacity: 1;
    transform: none;
  }
  .section .grid, .section .bento, .section .steps, .section .cost__rows, .section .tabs,
  .section .shots__frame, .section .trust__badges, .section .faq__list, .section .download__cards {
    margin-top: 28px;
  }
  .card, .bento__cell, .step, .dlcard { padding: 22px; }
  .terminal__body {
    padding: 16px;
    font-size: 12.5px;
  }
  .shots__frame { max-width: min(100%, 350px); }
  .dlcard__code {
    max-width: 100%;
    padding: 14px;
    font-size: 12px;
  }
  .footer {
    padding-block: 46px 28px;
  }
  .footer__top {
    gap: 30px;
  }
  .footer__cols {
    gap: 26px 24px;
  }
  .footer__col {
    gap: 9px;
  }
  .footer__col h4 {
    font-size: 11px;
    letter-spacing: .12em;
  }
  .footer__col a {
    font-size: 14px;
  }
  .footer__bottom {
    margin-top: 32px;
    gap: 14px;
  }
  .footer__legal {
    max-width: 34ch;
  }
}
@media (max-width: 360px) {
  .hero { padding-top: calc(var(--nav-h) + 20px); }
  .eyebrow { display: none; }
  .hero__cta .btn--lg {
    padding-inline: 6px;
    font-size: 13px;
  }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
  .reveal { opacity: 1; transform: none; }
  .window--hero { transform: none; }
}