/* 舞接龙 DanceChain — website.
   A night-stage page in the app's own colours: deep indigo, the three dragon colours from the icon
   (blue, purple, orange) for the three videos, and the app's rainbow "working" glow around the film.
   System fonts only (SF Pro / PingFang on Apple devices, fast in China, no web-font requests). */

:root {
  color-scheme: dark;
  --bg: #181514;              /* 朱墨: pine-soot ink */
  --bg-2: #1e1a17;
  --surface: #25201d;         /* night xuan-paper */
  --surface-2: #2e2824;
  --line: rgba(224, 184, 106, 0.14);
  --line-2: rgba(224, 184, 106, 0.28);
  --fg: #faf6ee;
  --muted: #9e968d;
  --faint: #7a7169;
  --accent: #e0b86a;          /* gold: links, markers */
  --accent-2: #d93829;        /* vermilion: buttons */
  --accent-ink: #26070f;
  --blue: #528bff;            /* video 1 (cobalt) */
  --purple: #a86bff;          /* video 2 (plum) */
  --orange: #ff8838;          /* video 3 (persimmon) */
  --pink: #ff375f;
  --green: #30d158;
  --radius: 26px;
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Hiragino Sans GB",
          "Noto Sans SC", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
  --display: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Hiragino Sans GB",
          "Noto Sans SC", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --rainbow: conic-gradient(from var(--spin, 0deg), #0a84ff, #5e5ce6, #bf5af2, #ff375f, #ff9f0a, #ffd60a, #0a84ff);
}

/* One page, two languages: html[data-lang] picks which [lang] blocks show. */
html[data-lang="zh"] [lang="en"],
html[data-lang="en"] [lang="zh"] { display: none !important; }

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; scroll-padding-top: 72px; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 400 17px/1.65 var(--font);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img, video { display: block; max-width: 100%; }
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { color: #b4b2ff; }
a:focus-visible, button:focus-visible, summary:focus-visible {
  outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 8px;
}
p { margin: 0; }
h1, h2, h3 { font-family: var(--display); margin: 0; letter-spacing: -0.022em; text-wrap: balance; }
html[data-lang="zh"] h1, html[data-lang="zh"] h2 { letter-spacing: 0; }
.wrap {
  max-width: 1120px;
  margin: 0 auto;
  padding-left: max(20px, env(safe-area-inset-left));
  padding-right: max(20px, env(safe-area-inset-right));
}
.eyebrow {
  font: 600 12px/1 var(--mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
}
html[data-lang="zh"] .eyebrow { font-family: var(--font); letter-spacing: 0.18em; font-size: 13px; text-transform: none; }
.muted { color: var(--muted); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

@property --spin { syntax: "<angle>"; inherits: true; initial-value: 0deg; }
@keyframes spin { to { --spin: 360deg; } }
@keyframes float { 50% { transform: translateY(-6px) rotate(var(--r, 0deg)); } }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 72%, transparent);
  backdrop-filter: saturate(160%) blur(18px);
  -webkit-backdrop-filter: saturate(160%) blur(18px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap { display: flex; align-items: center; gap: 16px; height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--fg); text-decoration: none; font: 700 18px/1 var(--display); white-space: nowrap; }
.brand:hover { color: var(--fg); }
.brand img { width: 32px; height: 32px; border-radius: 8px; box-shadow: 0 2px 10px rgba(0,0,0,.4); }
.brand small { font: 500 13px/1 var(--font); color: var(--faint); margin-left: 2px; }
.nav { margin-left: auto; display: flex; gap: 22px; font-size: 15px; }
.nav a { color: var(--muted); text-decoration: none; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--fg); }
.lang-switch { display: flex; padding: 3px; border-radius: 999px; background: var(--surface-2); border: 1px solid var(--line); }
.lang-switch button {
  appearance: none; border: 0; background: transparent; color: var(--muted); cursor: pointer;
  font: 600 13px/1 var(--font); padding: 7px 11px; border-radius: 999px; min-width: 40px;
}
html[data-lang="zh"] .lang-switch [data-set="zh"], html[data-lang="en"] .lang-switch [data-set="en"] {
  background: var(--fg); color: var(--bg);
}
@media (max-width: 760px) {
  .nav { display: none; }
  .lang-switch { margin-left: auto; }
  .brand small { display: none; }
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  padding: 14px 21px; border-radius: 999px; text-decoration: none; cursor: pointer;
  font: 600 16px/1 var(--font); border: 0; white-space: nowrap;
  transition: transform .15s ease, background .15s ease;
}
.btn:active { transform: scale(.97); }
.btn svg { width: 19px; height: 19px; flex: none; }
.btn-primary { background: linear-gradient(180deg, #d93829, #a8241a); color: #fff8f0; border-radius: 12px; box-shadow: 0 10px 30px -8px rgba(217,56,41,.55), inset 0 1px 0 rgba(255,255,255,.22); }
.btn-primary:hover { color: #fff; }
.btn-ghost { background: rgba(255,255,255,.06); color: var(--fg); border: 1px solid var(--line-2); }
.btn-ghost:hover { color: var(--fg); background: rgba(255,255,255,.1); }
.btn[aria-disabled="true"] { cursor: default; }
.btn[aria-disabled="true"]:active { transform: none; }

/* App Store QR: for people reading on a computer; phones just tap the button. */
.qr { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; color: var(--fg); margin-left: 6px; }
.qr img { width: 88px; height: 88px; background: #fff; padding: 6px; border-radius: 12px; box-shadow: 0 8px 24px -10px rgba(0,0,0,.6); }
.qr b { display: block; font-size: 14.5px; }
.qr small { display: block; color: var(--muted); font-size: 12.5px; margin-top: 2px; }
.qr-final { margin: 28px auto 0; display: flex; justify-content: center; }
.qr-final img { width: 120px; height: 120px; }
@media (hover: none) and (pointer: coarse) { .qr { display: none; } }
@media (max-width: 860px) { .qr { display: none; } }

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; }
.hero::before {
  content: ""; position: absolute; inset: -30% -20% auto; height: 900px; pointer-events: none; z-index: 0;
  background:
    radial-gradient(34% 40% at 20% 34%, rgba(217,56,41,.26), transparent 70%),
    radial-gradient(30% 36% at 78% 26%, rgba(224,184,106,.16), transparent 70%),
    radial-gradient(34% 34% at 62% 78%, rgba(168,107,255,.12), transparent 70%);
  filter: blur(30px);
}
.hero .wrap { position: relative; z-index: 1; display: grid; grid-template-columns: 1fr 1.08fr; gap: 56px; align-items: center; padding-block: 76px 84px; }
.hero h1 { font-size: clamp(40px, 5.6vw, 70px); line-height: 1.04; font-weight: 800; margin-top: 18px; }
html[data-lang="zh"] .hero h1 { line-height: 1.16; }
.hero h1 em {
  font-style: normal;
  background: linear-gradient(180deg, #f7df9c 0%, #d4a349 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.lede { margin-top: 22px; font-size: 19px; line-height: 1.6; color: var(--muted); max-width: 32em; }
.cta { margin-top: 32px; display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.chips { margin: 30px 0 0; padding: 0; list-style: none; display: flex; flex-wrap: wrap; gap: 8px; }
.chips li {
  display: inline-flex; align-items: center; gap: 7px;
  font-size: 14px; color: #e5e0e3; padding: 8px 13px; border-radius: 999px;
  background: rgba(255,255,255,.05); border: 1px solid var(--line);
}
.chips li i { width: 7px; height: 7px; border-radius: 50%; background: var(--c, var(--accent)); box-shadow: 0 0 10px var(--c, var(--accent)); }

/* Visual: the three phone videos fanned at the top, the finished film below in the app's rainbow glow. */
.stage { position: relative; }
.raws { position: relative; height: 0; padding-bottom: 27%; margin: 0 6% 0; }
.raw {
  --r: 0deg;
  position: absolute; top: 0; width: 38%; margin: 0;
  aspect-ratio: 16 / 9; border-radius: 14px; overflow: hidden;
  background: #111; border: 1px solid rgba(255,255,255,.18);
  box-shadow: 0 18px 40px -10px rgba(0,0,0,.7);
  transform: rotate(var(--r));
  animation: float 6s ease-in-out infinite;
}
.raw video, .raw img { width: 100%; height: 100%; object-fit: cover; }
.raw.r1 { left: 0; --r: -7deg; top: 8%; }
.raw.r2 { left: 31%; --r: 1.5deg; z-index: 2; animation-delay: -2s; }
.raw.r3 { right: 0; --r: 7deg; top: 9%; animation-delay: -4s; }
.badge {
  position: absolute; left: 8px; top: 8px; z-index: 2;
  width: 24px; height: 24px; border-radius: 50%;
  display: grid; place-items: center;
  font: 800 13px/1 var(--font); color: #fff;
  background: var(--c); box-shadow: 0 0 0 2px #fff, 0 4px 10px rgba(0,0,0,.4);
}
.raw .start {
  position: absolute; right: 8px; bottom: 7px; z-index: 2;
  font: 600 11px/1 var(--mono); color: #fff; padding: 5px 7px; border-radius: 7px;
  background: rgba(0,0,0,.55); backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
}
.merge {
  position: relative; z-index: 3; width: max-content; max-width: 92%; margin: 4% auto 4%;
  display: flex; align-items: center; gap: 9px; padding: 9px 16px; border-radius: 999px;
  font-size: 14px; font-weight: 600; color: var(--fg);
  background: linear-gradient(90deg, rgba(10,132,255,.22), rgba(191,90,242,.22), rgba(255,159,10,.2));
  border: 1px solid var(--line-2);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
}
.merge svg { width: 17px; height: 17px; color: #ffd60a; flex: none; }
.film { position: relative; margin: 0; }
.film-frame {
  position: relative; border-radius: 22px; padding: 1px;
  background: rgba(255,255,255,.14);
  box-shadow: 0 24px 60px rgba(0,0,0,.65), 0 0 40px rgba(224,184,106,.16);
}
.film-frame video, .film-frame img {
  width: 100%; aspect-ratio: 16 / 9; object-fit: cover; border-radius: 20px; background: #000;
}
.film-bar {
  margin-top: 14px; display: grid; grid-template-columns: auto 1fr; gap: 8px 12px; align-items: center;
  font-size: 13.5px; color: var(--muted);
}
.film-bar .done { display: inline-flex; align-items: center; gap: 7px; color: var(--fg); font-weight: 600; }
.film-bar .done svg { width: 18px; height: 18px; color: var(--green); }
.film-bar .time { justify-self: end; font: 500 12px/1 var(--mono); color: var(--faint); }
.legs { grid-column: 1 / -1; position: relative; display: flex; gap: 3px; height: 8px; }
.legs i { display: block; height: 100%; border-radius: 4px; background: var(--c); opacity: .85; }
.legs .head {
  position: absolute; top: -4px; width: 3px; height: 16px; border-radius: 2px; background: #fff;
  box-shadow: 0 0 8px rgba(255,255,255,.9); left: 0; transition: left .25s linear;
}
@media (max-width: 920px) {
  /* Phones: headline, then the film, then the words — the result is the pitch. */
  .hero .wrap { display: flex; flex-direction: column; gap: 0; padding-block: 44px 60px; }
  .hero-copy { display: contents; }
  .hero .eyebrow { order: 1; }
  .hero h1 { order: 2; }
  .stage { order: 3; max-width: 600px; width: 100%; margin: 34px auto 0; }
  .lede { order: 4; margin-top: 30px; }
  .cta { order: 5; }
  .chips { order: 6; }
}

/* ---------- Sections ---------- */
section.block { position: relative; padding-block: 96px; border-top: 1px solid var(--line); }
.head { display: grid; gap: 14px; margin-bottom: 44px; max-width: 44em; }
.head.center { text-align: center; margin-inline: auto; justify-items: center; }
.head h2 { font-size: clamp(30px, 4.2vw, 48px); line-height: 1.1; font-weight: 800; }
html[data-lang="zh"] .head h2 { line-height: 1.25; }
.head p { color: var(--muted); font-size: 18px; }
@media (max-width: 760px) { section.block { padding-block: 72px; } }

/* Steps */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; list-style: none; padding: 0; margin: 0; counter-reset: step; }
.steps li {
  position: relative; overflow: hidden;
  background: linear-gradient(180deg, var(--surface-2), var(--surface));
  border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 24px 28px;
  display: grid; gap: 10px; align-content: start;
}
.steps li::before {
  counter-increment: step; content: counter(step);
  width: 34px; height: 34px; border-radius: 50%; display: grid; place-items: center;
  font: 800 16px/1 var(--display); color: #fff; background: var(--c);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--c) 30%, transparent), 0 8px 20px -4px var(--c);
}
.steps li::after {
  content: ""; position: absolute; right: -40px; top: -40px; width: 140px; height: 140px; border-radius: 50%;
  background: radial-gradient(var(--c), transparent 70%); opacity: .14; pointer-events: none;
}
.steps h3 { font-size: 21px; line-height: 1.3; }
.steps p { color: var(--muted); font-size: 15.5px; }
@media (max-width: 820px) { .steps { grid-template-columns: 1fr; } }

/* Showcase rows: copy on one side, a visual on the other */
.show { display: grid; grid-template-columns: 1fr 1.15fr; gap: 64px; align-items: center; }
.show + .show { margin-top: 110px; }
.show.flip .show-copy { order: 2; }
.show-copy { display: grid; gap: 16px; align-content: start; }
.show-copy h2 { font-size: clamp(28px, 3.6vw, 42px); line-height: 1.12; font-weight: 800; }
html[data-lang="zh"] .show-copy h2 { line-height: 1.28; }
.show-copy > p { color: var(--muted); font-size: 17.5px; }
.ticks { list-style: none; margin: 6px 0 0; padding: 0; display: grid; gap: 10px; }
.ticks li { display: flex; gap: 11px; color: var(--muted); font-size: 15.5px; }
.ticks li::before { content: ""; flex: none; margin-top: 8px; width: 9px; height: 9px; border-radius: 50%; background: var(--c, var(--accent)); box-shadow: 0 0 10px var(--c, var(--accent)); }
.panel {
  position: relative; border-radius: var(--radius); overflow: hidden;
  background: linear-gradient(180deg, var(--surface-2), var(--surface));
  border: 1px solid var(--line); padding: 22px;
  box-shadow: 0 30px 80px -30px rgba(0,0,0,.8);
}
@media (max-width: 920px) {
  .show { grid-template-columns: 1fr; gap: 32px; }
  .show.flip .show-copy { order: 0; }
  .show + .show { margin-top: 80px; }
}

/* AI panel: which video dances which part + the highlight curve, like the app's result card */
.result-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin-bottom: 14px; }
.result-head b { font-size: 17px; }
.result-head span { font-size: 13px; color: var(--faint); }
.thumbs { display: flex; gap: 4px; height: 76px; }
.thumbs figure { position: relative; margin: 0; border-radius: 10px; overflow: hidden; border: 2.5px solid var(--c); min-width: 0; }
.thumbs img { width: 100%; height: 100%; object-fit: cover; }
.thumbs .badge { left: 6px; top: auto; bottom: 6px; width: 20px; height: 20px; font-size: 11px; box-shadow: 0 0 0 1.5px #fff; }
.thumbs .who {
  position: absolute; left: 31px; bottom: 7px; display: inline-flex; align-items: center; gap: 3px;
  font: 700 11.5px/1 var(--font); color: #fff; padding: 3px 7px 3px 5px; border-radius: 6px;
  background: rgba(0,0,0,.55); white-space: nowrap;
}
.thumbs .who svg { width: 11px; height: 11px; }
.axis { display: flex; justify-content: space-between; font: 500 11.5px/1 var(--mono); color: var(--faint); margin-top: 8px; }
.curve-label { margin: 20px 0 6px; font-size: 13px; color: var(--muted); font-weight: 600; }
.curve { width: 100%; height: 92px; overflow: visible; }
.reasons { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.reasons > span {
  display: inline-flex; align-items: center; gap: 7px; font-size: 13px; color: var(--fg);
  padding: 6px 11px; border-radius: 999px; background: rgba(255,255,255,.06); border: 1px solid var(--line);
}
.reasons > span i { width: 8px; height: 8px; border-radius: 50%; background: var(--c); }
.reasons > span em { font-style: normal; font-family: var(--mono); font-size: 12px; color: var(--faint); }

/* Song panel: the room recording vs the original track */
.wave-row { display: grid; gap: 10px; }
.wave-row + .wave-row { margin-top: 26px; }
.wave-label { display: flex; align-items: center; justify-content: space-between; gap: 8px; font-size: 14px; font-weight: 600; }
.wave-label .tag { font: 600 11.5px/1 var(--font); padding: 5px 9px; border-radius: 999px; white-space: nowrap; }
.tag.bad { color: #ffb4b4; background: rgba(255,69,58,.14); border: 1px solid rgba(255,69,58,.3); }
.tag.good { color: #9ff2b9; background: rgba(48,209,88,.13); border: 1px solid rgba(48,209,88,.3); }
.wave { position: relative; display: flex; align-items: center; gap: 2px; height: 64px; }
.wave i { flex: 1; min-width: 1px; border-radius: 2px; background: #5d5872; height: var(--h, 30%); }
.wave i.talk { background: #ffb340; }
.wave.song i { background: linear-gradient(180deg, #5aa8ff, #b18cff 60%, #ff8fb0); }
.wave .noise {
  position: absolute; top: -14px; font-size: 11.5px; font-weight: 600; color: #ffcf8a; white-space: nowrap;
  padding: 3px 8px; border-radius: 8px; background: rgba(30,20,10,.9); border: 1px solid rgba(255,159,10,.35);
  transform: translateX(-50%);
}
.sync { display: flex; align-items: center; gap: 10px; margin-top: 24px; padding: 12px 14px; border-radius: 14px; background: rgba(48,209,88,.08); border: 1px solid rgba(48,209,88,.22); font-size: 14px; color: #c8f5d5; }
.sync svg { width: 20px; height: 20px; flex: none; color: var(--green); }

/* Demo video */
.demo-frame {
  position: relative; max-width: 980px; margin: 0 auto; border-radius: 24px; overflow: hidden;
  background: #000; border: 1px solid var(--line-2);
  box-shadow: 0 40px 120px -30px rgba(94,92,230,.55), 0 0 0 1px rgba(255,255,255,.03);
}
.demo-frame video { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.demo-toggle {
  position: absolute; right: 14px; bottom: 14px; width: 44px; height: 44px; border-radius: 50%;
  display: grid; place-items: center; border: 1px solid rgba(255,255,255,.25); cursor: pointer;
  color: #fff; background: rgba(0,0,0,.45); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
}
.demo-toggle svg { width: 20px; height: 20px; }
.demo-toggle .i-play, .demo-toggle.paused .i-pause { display: none; }
.demo-toggle.paused .i-play { display: block; }

/* Feature grid */
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 34px 36px; }
.feature { display: grid; grid-template-columns: 44px 1fr; gap: 4px 16px; align-items: start; }
.feature .ico {
  grid-row: span 2; width: 44px; height: 44px; border-radius: 13px; display: grid; place-items: center;
  color: var(--c, var(--accent)); background: color-mix(in srgb, var(--c, var(--accent)) 14%, var(--surface));
  border: 1px solid color-mix(in srgb, var(--c, var(--accent)) 30%, transparent);
}
.feature .ico svg { width: 22px; height: 22px; }
.feature h3 { font: 650 17px/1.35 var(--font); letter-spacing: 0; }
.feature h3 small { font: 700 11px/1 var(--font); color: #e3b341; vertical-align: middle; margin-left: 6px; padding: 2px 6px; border: 1px solid rgba(227,179,65,.5); border-radius: 999px; }
.feature p { color: var(--muted); font-size: 15px; }
@media (max-width: 900px) { .features { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .features { grid-template-columns: 1fr; gap: 26px; } }

/* Pricing */
.plans { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.plan { position: relative; border: 1px solid var(--line); border-radius: var(--radius); padding: 30px; display: grid; gap: 16px; align-content: start; background: var(--surface); }
.plan.pro { border-color: transparent; background: linear-gradient(165deg, rgba(143,140,255,.2), var(--surface) 55%); }
.plan.pro::before {
  content: ""; position: absolute; inset: -1px; border-radius: inherit; padding: 1.5px; pointer-events: none;
  background: var(--rainbow); animation: spin 8s linear infinite;
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor; mask-composite: exclude;
}
.plan .name { display: flex; align-items: center; gap: 10px; font: 700 15px/1 var(--font); color: var(--muted); }
.plan .name .pill { font: 700 11px/1 var(--font); color: #2a1d00; background: #ffd60a; padding: 5px 8px; border-radius: 999px; letter-spacing: .02em; }
.plan.life { background: linear-gradient(165deg, rgba(255,214,10,.14), var(--surface) 55%); border-color: rgba(255,214,10,.35); }
.plan .name .pill.gold { background: linear-gradient(90deg, #ffd60a, #ff9f0a); }
.plan.life li::before { color: #ffd60a; }
.plan .price { font: 800 clamp(28px, 2.6vw, 36px)/1.15 var(--display); letter-spacing: -0.02em; }
.plan .price small { font: 500 15px/1 var(--font); color: var(--muted); margin-left: 8px; letter-spacing: 0; }
.plan ul { margin: 0; padding: 0; list-style: none; display: grid; gap: 10px; color: var(--muted); font-size: 15.5px; }
.plan li { display: flex; gap: 10px; }
.plan li::before { content: "✓"; color: var(--accent); font-weight: 800; }
.plan .fine { font-size: 13px; color: var(--faint); }
@media (max-width: 900px) { .plans { grid-template-columns: 1fr; max-width: 560px; } }

/* Privacy promise band */
.promise { position: relative; border-radius: 30px; padding: 44px; overflow: hidden; background: linear-gradient(135deg, #14122a, #0f0d1d); border: 1px solid var(--line); }
.promise::before { content: ""; position: absolute; right: -120px; top: -160px; width: 420px; height: 420px; border-radius: 50%; background: radial-gradient(rgba(48,209,88,.2), transparent 70%); }
.promise-grid { position: relative; display: grid; grid-template-columns: 1.1fr 1fr; gap: 40px; align-items: center; }
.promise h2 { font-size: clamp(28px, 3.4vw, 40px); line-height: 1.15; font-weight: 800; }
html[data-lang="zh"] .promise h2 { line-height: 1.3; }
.promise p { color: var(--muted); margin-top: 14px; }
.promise .btn { margin-top: 24px; }
.promise ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; }
.promise li { display: flex; gap: 14px; align-items: flex-start; padding: 16px; border-radius: 18px; background: rgba(255,255,255,.04); border: 1px solid var(--line); }
.promise li svg { width: 24px; height: 24px; flex: none; color: var(--green); margin-top: 1px; }
.promise li b { display: block; font-size: 15.5px; }
.promise li span { color: var(--muted); font-size: 14.5px; }
@media (max-width: 860px) { .promise { padding: 30px 22px; } .promise-grid { grid-template-columns: 1fr; gap: 26px; } }

/* FAQ */
.faq { max-width: 820px; }
details { border-bottom: 1px solid var(--line); padding-block: 18px; }
details:first-of-type { border-top: 1px solid var(--line); }
summary { cursor: pointer; list-style: none; display: flex; justify-content: space-between; gap: 18px; font-weight: 650; font-size: 17px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; flex: none; color: var(--accent); font: 500 22px/1 var(--mono); transition: transform .2s; }
details[open] summary::after { transform: rotate(45deg); }
details p { margin-top: 10px; color: var(--muted); font-size: 16px; }
.more { margin-top: 22px; font-size: 15px; }

/* Final call */
.final { text-align: center; padding-block: 110px 120px; position: relative; overflow: hidden; }
.final::before { content: ""; position: absolute; left: 50%; top: 50%; width: 900px; height: 500px; transform: translate(-50%, -50%); background: radial-gradient(closest-side, rgba(94,92,230,.35), transparent); pointer-events: none; }
.final .icon { width: 96px; height: 96px; border-radius: 22px; margin: 0 auto 26px; box-shadow: 0 20px 50px -10px rgba(217,56,41,.6); position: relative; }
.final h2 { position: relative; font-size: clamp(32px, 4.6vw, 54px); line-height: 1.1; font-weight: 800; }
html[data-lang="zh"] .final h2 { line-height: 1.25; }
.final p { position: relative; color: var(--muted); margin: 16px auto 0; max-width: 30em; font-size: 18px; }
.final .cta { justify-content: center; position: relative; }

/* Footer */
.site-footer { border-top: 1px solid var(--line); padding-block: 40px 52px; color: var(--faint); font-size: 14px; }
.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 18px 32px; align-items: center; justify-content: space-between; }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 8px 22px; }
.site-footer a { color: var(--muted); text-decoration: none; }
.site-footer a:hover { color: var(--fg); }
.mail { font-family: var(--mono); font-size: 13.5px; }

/* ---------- Document pages (privacy, terms, support) ---------- */
.doc-hero { position: relative; overflow: hidden; border-bottom: 1px solid var(--line); }
.doc-hero::before {
  content: ""; position: absolute; inset: -40% -20% auto; height: 600px; pointer-events: none;
  background: radial-gradient(30% 50% at 25% 40%, rgba(10,132,255,.25), transparent 70%),
              radial-gradient(30% 50% at 75% 30%, rgba(191,90,242,.22), transparent 70%);
  filter: blur(30px);
}
.doc-hero .wrap { position: relative; padding-block: 72px 56px; display: grid; gap: 16px; max-width: 880px; }
.doc-hero h1 { font-size: clamp(36px, 5vw, 56px); line-height: 1.1; font-weight: 800; }
html[data-lang="zh"] .doc-hero h1 { line-height: 1.25; }
.doc-hero p { color: var(--muted); font-size: 18px; max-width: 36em; }
.doc-hero .updated { font: 500 12.5px/1 var(--mono); color: var(--faint); letter-spacing: .06em; }
.doc { max-width: 880px; padding-block: 56px 96px; }
.cards3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-bottom: 56px; }
.cards3 > div { padding: 22px; border-radius: 20px; background: linear-gradient(180deg, var(--surface-2), var(--surface)); border: 1px solid var(--line); display: grid; gap: 8px; align-content: start; }
.cards3 svg { width: 28px; height: 28px; color: var(--c, var(--green)); }
.cards3 b { font-size: 16.5px; line-height: 1.35; }
.cards3 span { color: var(--muted); font-size: 14.5px; line-height: 1.55; }
@media (max-width: 760px) { .cards3 { grid-template-columns: 1fr; } }
.doc h2 { font-size: 23px; line-height: 1.3; margin: 44px 0 12px; letter-spacing: -0.01em; scroll-margin-top: 80px; }
.doc h2:first-of-type { margin-top: 0; }
.doc p, .doc li { color: var(--muted); font-size: 16.5px; }
.doc p + p { margin-top: 12px; }
.doc ul { margin: 10px 0 0; padding-left: 22px; display: grid; gap: 8px; }
.doc li::marker { color: var(--accent); }
.doc strong { color: var(--fg); font-weight: 650; }
.doc .note { margin-top: 44px; padding: 20px 22px; border-radius: 18px; background: var(--surface); border: 1px solid var(--line); }
.doc .toc { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 44px; padding: 0; list-style: none; }
.toc a { display: inline-block; font-size: 14px; color: var(--muted); text-decoration: none; padding: 7px 13px; border-radius: 999px; background: rgba(255,255,255,.05); border: 1px solid var(--line); }
.toc a:hover { color: var(--fg); }

/* Contact card on support */
.contact { display: grid; grid-template-columns: 1fr auto; gap: 18px; align-items: center; padding: 26px; border-radius: 22px; background: linear-gradient(135deg, rgba(143,140,255,.16), var(--surface) 60%); border: 1px solid var(--line-2); margin-bottom: 56px; }
.contact b { font-size: 19px; }
.contact p { margin-top: 6px; }
@media (max-width: 640px) { .contact { grid-template-columns: 1fr; } }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}

/* Why not an editing app: three-column comparison */
.compare { display: grid; gap: 8px; max-width: 980px; }
.compare .row { display: grid; grid-template-columns: 1.1fr 1.4fr 1.4fr; gap: 12px; align-items: center; padding: 14px 18px; border-radius: 14px; background: rgba(255,255,255,.04); border: 1px solid rgba(255,255,255,.07); font-size: 15.5px; color: var(--muted); }
.compare .row > span:first-child { color: var(--fg); font-weight: 650; }
.compare .row .us { color: var(--fg); font-weight: 650; position: relative; padding-left: 26px; }
.compare .row .us::before { content: ""; position: absolute; left: 0; top: 50%; width: 16px; height: 16px; margin-top: -8px; border-radius: 50%; background: linear-gradient(135deg, var(--blue), var(--purple)); box-shadow: 0 0 0 3px rgba(124,106,255,.18); }
.compare .row.head { background: none; border: 0; padding-top: 0; padding-bottom: 4px; font-size: 13px; letter-spacing: .04em; text-transform: uppercase; }
.compare .row.head .us::before { display: none; }
.compare .row.head .us { padding-left: 0; }
@media (max-width: 720px) {
  .compare .row { grid-template-columns: 1fr; gap: 4px; }
  .compare .row.head { display: none; }
  .compare .row > span:nth-child(2)::before { content: "手动："; opacity: .7; }
  html[data-lang="en"] .compare .row > span:nth-child(2)::before { content: "By hand: "; }
}

.site-footer .beian{text-align:center;font-size:12px;opacity:.7;margin:12px 0 0}
.site-footer .beian a{color:inherit;margin:0 6px}