:root {
  --bg: #06080f;
  --bg-2: #0b1020;
  --glass: rgba(255, 255, 255, 0.045);
  --glass-strong: rgba(255, 255, 255, 0.07);
  --line: rgba(255, 255, 255, 0.09);
  --line-strong: rgba(255, 255, 255, 0.16);
  --text: #eef1f8;
  --muted: #98a2bb;
  --accent: #4f8cff;
  --violet: #8b5cf6;
  --mint: #2ee6c8;
  --pos: #34d399;
  --neg: #fb7185;
  --grad: linear-gradient(100deg, #7aa7ff 0%, #a78bfa 45%, #2ee6c8 100%);
  --radius: 20px;
}
* { box-sizing: border-box; }
html { overflow-x: clip; -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 80px; }
body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  overflow-x: hidden;
  overflow-x: clip;
}

/* Background: slow-moving aurora glow + a faint grid that fades out */
body::before, body::after { content: ""; position: fixed; inset: 0; z-index: -1; pointer-events: none; }
body::before {
  background:
    radial-gradient(40% 35% at 15% 10%, rgba(79, 140, 255, 0.30), transparent 70%),
    radial-gradient(35% 35% at 85% 15%, rgba(139, 92, 246, 0.28), transparent 70%),
    radial-gradient(45% 40% at 60% 90%, rgba(46, 230, 200, 0.14), transparent 70%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
  filter: blur(20px);
  animation: aurora 24s ease-in-out infinite alternate;
}
body::after {
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 30%, transparent 75%);
  mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 30%, transparent 75%);
}
@keyframes aurora {
  0% { transform: translate3d(0, 0, 0) scale(1); }
  50% { transform: translate3d(-3%, 2%, 0) scale(1.08); }
  100% { transform: translate3d(3%, -2%, 0) scale(1.04); }
}

a { color: #8fb4ff; text-decoration: none; }
a:hover { color: #b9d0ff; }
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 20px; }
.muted { color: var(--muted); }
.pos { color: var(--pos); }
.neg { color: var(--neg); }
.glass {
  background: linear-gradient(180deg, var(--glass-strong), var(--glass));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06) inset, 0 30px 60px -30px rgba(0, 0, 0, 0.6);
}

/* Nav */
.topbar {
  position: sticky; top: 0; z-index: 10;
  background: rgba(6, 8, 15, 0.6);
  -webkit-backdrop-filter: blur(14px); backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding-top: 14px; padding-bottom: 14px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); font-weight: 800; font-size: 20px; letter-spacing: -0.01em; }
.brand:hover { color: var(--text); }
.nav nav { display: flex; align-items: center; gap: 24px; flex-wrap: wrap; }
.nav nav a { color: var(--muted); font-weight: 500; font-size: 15px; }
.nav nav a:hover { color: var(--text); }
.nav nav .nav-cta { color: var(--text); padding: 8px 16px; border: 1px solid var(--line-strong); border-radius: 999px; background: var(--glass); }
.nav nav .nav-cta:hover { border-color: #7aa7ff; }

/* Buttons and small bits */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 14px 24px; border-radius: 14px; font-weight: 700; font-size: 16px; transition: transform .2s, box-shadow .2s, border-color .2s; }
.btn:hover { transform: translateY(-2px); }
.btn.primary { color: #fff; background: linear-gradient(135deg, #4f8cff, #8b5cf6); box-shadow: 0 10px 30px -8px rgba(99, 102, 241, 0.7); }
.btn.primary:hover { color: #fff; box-shadow: 0 14px 36px -8px rgba(99, 102, 241, 0.9); }
.btn.ghost { color: var(--text); border: 1px solid var(--line-strong); background: var(--glass); }
.btn.ghost:hover { color: var(--text); border-color: #7aa7ff; }
.pill { display: inline-flex; align-items: center; gap: 10px; padding: 6px 14px; border-radius: 999px; border: 1px solid var(--line-strong); background: var(--glass); font-size: 14px; font-weight: 600; color: #cfd8ee; }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--mint); box-shadow: 0 0 0 0 rgba(46, 230, 200, 0.6); animation: ping 2s infinite; }
@keyframes ping { 70% { box-shadow: 0 0 0 10px rgba(46, 230, 200, 0); } 100% { box-shadow: 0 0 0 0 rgba(46, 230, 200, 0); } }
.tag { display: inline-block; padding: 3px 10px; border-radius: 999px; font-size: 12px; font-weight: 700; background: rgba(255, 255, 255, 0.08); color: #cfd8ee; white-space: nowrap; }
.tag.green { background: rgba(52, 211, 153, 0.15); color: var(--pos); }
.tag.red { background: rgba(251, 113, 133, 0.15); color: var(--neg); }
.grad { background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.eyebrow { margin: 0 0 12px; font-size: 13px; font-weight: 700; letter-spacing: 0.14em; text-transform: uppercase; color: var(--mint); }

/* Hero */
.hero { display: grid; grid-template-columns: 1.15fr 1fr; gap: 56px; align-items: center; padding-top: 88px; padding-bottom: 96px; }
h1 { font-size: clamp(40px, 6.4vw, 72px); line-height: 1.03; letter-spacing: -0.035em; font-weight: 800; margin: 22px 0 22px; }
.lead { color: var(--muted); font-size: 19px; max-width: 560px; margin: 0 0 32px; }
.lead q { color: var(--text); quotes: "\201C" "\201D"; }
.cta { display: flex; gap: 14px; flex-wrap: wrap; }
.chips { display: flex; flex-wrap: wrap; gap: 10px 22px; list-style: none; padding: 0; margin: 36px 0 0; color: var(--muted); font-size: 14px; font-weight: 600; }
.chips li { display: flex; align-items: center; gap: 8px; }
.chips li::before { content: ""; width: 16px; height: 16px; border-radius: 50%; background: rgba(46, 230, 200, 0.15) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath fill='%232ee6c8' d='m9.5 16.2-4-4 1.4-1.4 2.6 2.6 6.6-6.6 1.4 1.4z'/%3E%3C/svg%3E") center/12px no-repeat; }

.hero-art { position: relative; display: grid; place-items: center; min-height: 480px; }
.halo { position: absolute; width: 380px; height: 380px; border-radius: 50%; background: conic-gradient(from 0deg, #4f8cff, #8b5cf6, #2ee6c8, #4f8cff); filter: blur(70px); opacity: 0.45; animation: spin 18s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.hero-logo { position: relative; width: 380px; max-width: 80%; margin: -90px 0 0 60px; height: auto; filter: drop-shadow(0 30px 40px rgba(0, 0, 0, 0.55)); animation: float 6s ease-in-out infinite; }
@keyframes float { 50% { transform: translateY(-12px); } }
.voice-card { position: absolute; left: -10px; bottom: 6px; width: min(330px, 92%); padding: 16px 18px; }
.vc-head { display: flex; align-items: center; gap: 12px; }
.mic { display: grid; place-items: center; width: 36px; height: 36px; flex: none; border-radius: 50%; background: linear-gradient(135deg, #4f8cff, #8b5cf6); }
.mic svg { width: 18px; height: 18px; fill: #fff; }
.mic.sm { width: 28px; height: 28px; }
.mic.sm svg { width: 14px; height: 14px; }
.wave { display: flex; align-items: center; gap: 4px; height: 24px; }
.wave i { width: 4px; height: 100%; border-radius: 2px; background: var(--grad); animation: wave 1.1s ease-in-out infinite; }
.wave i:nth-child(2) { animation-delay: .1s; } .wave i:nth-child(3) { animation-delay: .2s; } .wave i:nth-child(4) { animation-delay: .3s; }
.wave i:nth-child(5) { animation-delay: .4s; } .wave i:nth-child(6) { animation-delay: .5s; } .wave i:nth-child(7) { animation-delay: .6s; }
@keyframes wave { 0%, 100% { transform: scaleY(.3); } 50% { transform: scaleY(1); } }
.vc-quote { margin: 12px 0; font-size: 14px; color: #dfe5f3; }
.vc-result { display: flex; align-items: center; gap: 6px; flex-wrap: wrap; }
.vc-result strong { margin-left: auto; }

/* Sections */
.section { padding-top: 40px; padding-bottom: 80px; }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 40px; }
.section-head h2, .cta-band h2 { font-size: clamp(30px, 4.4vw, 46px); line-height: 1.12; letter-spacing: -0.03em; font-weight: 800; margin: 0; }

/* Tabs */
.tabs { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; margin-bottom: 20px; }
.tabs button {
  display: inline-flex; align-items: center; gap: 8px; padding: 11px 18px; border-radius: 999px; cursor: pointer;
  font: 600 15px/1 inherit; font-family: inherit; color: var(--muted);
  background: var(--glass); border: 1px solid var(--line); transition: color .2s, border-color .2s, background .2s;
}
.tabs button svg { width: 18px; height: 18px; fill: currentColor; }
.tabs button:hover { color: var(--text); border-color: var(--line-strong); }
.tabs button[aria-selected="true"] { color: #fff; border-color: transparent; background: linear-gradient(135deg, rgba(79, 140, 255, 0.9), rgba(139, 92, 246, 0.9)); box-shadow: 0 8px 24px -8px rgba(99, 102, 241, 0.8); }
.tabs button:focus-visible { outline: 2px solid var(--mint); outline-offset: 3px; }

.panels { padding: 44px; min-height: 470px; display: grid; align-items: center; }
.panel { display: grid; grid-template-columns: 1.1fr 1fr; gap: 48px; align-items: center; animation: fade .35s ease; }
.panel[hidden] { display: none; }
@keyframes fade { from { opacity: 0; transform: translateY(8px); } }
.panel h3 { font-size: clamp(24px, 3vw, 32px); letter-spacing: -0.02em; margin: 0 0 14px; }
.panel p { color: var(--muted); font-size: 17px; margin: 0 0 20px; }
.ticks { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.ticks li { position: relative; padding-left: 32px; color: #d3d9e8; }
.ticks li::before { content: ""; position: absolute; left: 0; top: 3px; width: 20px; height: 20px; border-radius: 50%; background: rgba(79, 140, 255, 0.16) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath fill='%237aa7ff' d='m9.5 16.2-4-4 1.4-1.4 2.6 2.6 6.6-6.6 1.4 1.4z'/%3E%3C/svg%3E") center/14px no-repeat; }

/* Feature mock-ups */
.mock { background: rgba(5, 8, 16, 0.65); border: 1px solid var(--line); border-radius: 18px; padding: 22px; display: grid; gap: 12px; box-shadow: 0 30px 60px -30px rgba(0, 0, 0, 0.8); }
.mock-title { display: flex; justify-content: space-between; align-items: center; gap: 12px; font-weight: 700; }
.mock-title .muted { font-weight: 500; font-size: 14px; }
.mock-row { display: flex; align-items: center; gap: 10px; color: #dfe5f3; font-size: 14px; }
.draft { display: flex; align-items: center; gap: 10px; padding: 12px 14px; border-radius: 12px; background: rgba(255, 255, 255, 0.04); border: 1px solid var(--line); font-size: 14px; }
.draft strong { margin-left: auto; }
.mock-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 4px; }
.btn-mini { padding: 8px 14px; border-radius: 10px; font-size: 13px; font-weight: 700; border: 1px solid var(--line-strong); }
.btn-mini.solid { border-color: transparent; background: linear-gradient(135deg, #4f8cff, #8b5cf6); }
.bars { display: flex; align-items: flex-end; gap: 8px; height: 150px; padding-top: 8px; }
.bars i { flex: 1; height: var(--h); border-radius: 6px 6px 3px 3px; background: linear-gradient(180deg, #7aa7ff, rgba(139, 92, 246, 0.35)); }
.stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.stats div { display: grid; padding: 12px; border-radius: 12px; background: rgba(255, 255, 255, 0.04); font-size: 13px; }
.stats strong { font-size: 18px; }
.docs { position: relative; min-height: 260px; place-items: center; }
.doc-card { position: absolute; width: 62%; display: grid; gap: 10px; padding: 20px; border-radius: 14px; border: 1px solid var(--line-strong); background: linear-gradient(180deg, #151b2e, #0d1222); }
.doc-card.back { transform: translate(18%, -12%) rotate(6deg); opacity: 0.7; }
.doc-card.front { transform: translate(-8%, 6%) rotate(-3deg); box-shadow: 0 30px 50px -20px rgba(0, 0, 0, 0.8); }
.doc-card .muted { font-size: 13px; }
.lines { display: grid; gap: 8px; }
.lines i { height: 8px; border-radius: 4px; background: rgba(255, 255, 255, 0.08); }
.lines i:nth-child(2n) { width: 75%; }
.pdf { justify-self: start; padding: 4px 12px; border-radius: 8px; font-size: 13px; font-weight: 700; background: rgba(251, 113, 133, 0.15); color: var(--neg); }
.table { display: grid; }
.table div { display: grid; grid-template-columns: 1fr auto 90px; gap: 12px; padding: 12px 4px; border-bottom: 1px solid var(--line); font-size: 14px; }
.table strong { text-align: right; }
.table .total { border-bottom: 0; font-weight: 700; }
.months { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; }
.months span { padding: 14px 0; text-align: center; border-radius: 12px; font-weight: 700; font-size: 14px; color: var(--muted); background: rgba(255, 255, 255, 0.03); border: 1px dashed var(--line-strong); }
.months .on { color: var(--pos); border: 1px solid rgba(52, 211, 153, 0.3); background: rgba(52, 211, 153, 0.1); }
.months .now { box-shadow: 0 0 0 2px var(--pos); }
.lang { grid-template-columns: 1fr 1fr; }
.lang-card { display: grid; gap: 6px; padding: 18px; border-radius: 14px; background: rgba(255, 255, 255, 0.04); border: 1px solid var(--line); }
.lang-card .tag { justify-self: start; }
.lang-card b { font-size: 18px; }
.lang-card .muted { font-size: 13px; }

/* Steps */
.steps { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.steps li { padding: 28px; transition: transform .25s, border-color .25s; }
.steps li:hover { transform: translateY(-4px); border-color: var(--line-strong); }
.num { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 12px; font-weight: 800; background: linear-gradient(135deg, #4f8cff, #8b5cf6); margin-bottom: 18px; }
.steps h3 { margin: 0 0 8px; font-size: 20px; }
.steps p { margin: 0; color: var(--muted); }

/* CTA band */
.cta-band { display: flex; align-items: center; gap: 28px; padding: 40px 44px; background: linear-gradient(120deg, rgba(79, 140, 255, 0.18), rgba(139, 92, 246, 0.16) 50%, rgba(46, 230, 200, 0.10)); }
.cta-band > div { flex: 1; }
.cta-band p { margin: 8px 0 0; }

/* Document pages (privacy, delete account) */
.doc { max-width: 780px; padding-top: 56px; padding-bottom: 80px; }
.doc h1 { font-size: clamp(32px, 5vw, 48px); }
.doc h2 { font-size: 21px; margin-top: 36px; }
.doc p, .doc li { color: var(--muted); }
.doc strong { color: var(--text); }
.doc ol, .doc ul { padding-left: 22px; }
.note { background: var(--glass); border: 1px solid var(--line); border-radius: 14px; padding: 16px 18px; }

.foot { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; border-top: 1px solid var(--line); padding-top: 28px; padding-bottom: 36px; color: var(--muted); font-size: 14px; }
.foot nav { display: flex; gap: 20px; flex-wrap: wrap; }
.foot nav a { color: var(--muted); }
.foot nav a:hover { color: var(--text); }

@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; gap: 24px; padding-top: 48px; padding-bottom: 64px; }
  .hero-art { min-height: 0; padding-top: 12px; }
  .hero-logo { width: 280px; margin: 0; }
  .voice-card { position: relative; left: auto; bottom: auto; margin-top: -24px; }
  .halo { width: 280px; height: 280px; }
  .panel { grid-template-columns: 1fr; gap: 32px; }
  .panels { padding: 28px; min-height: 0; }
  .steps { grid-template-columns: 1fr; }
  .cta-band { flex-direction: column; text-align: center; padding: 32px 24px; }
}
@media (max-width: 640px) {
  .nav nav a:not(.nav-cta) { display: none; }
  .tabs { flex-wrap: nowrap; justify-content: flex-start; overflow-x: auto; margin: 0 -20px 16px; padding: 4px 20px; scrollbar-width: none; }
  .tabs::-webkit-scrollbar { display: none; }
  .tabs button { flex: none; }
  .panels { padding: 22px 18px; }
  .lang { grid-template-columns: 1fr; }
  .doc-card { width: 78%; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}

/* Language switch */
.lang-toggle {
  font: 700 14px/1 inherit; font-family: inherit; color: var(--text); cursor: pointer;
  padding: 8px 12px; border-radius: 999px; border: 1px solid var(--line-strong); background: var(--glass);
  transition: border-color .2s;
}
.lang-toggle:hover { border-color: #2ee6c8; }
.lang-toggle:focus-visible { outline: 2px solid var(--mint); outline-offset: 3px; }
html[lang="zh-CN"] h1 { letter-spacing: 0; line-height: 1.18; font-size: clamp(38px, 5.4vw, 64px); }
html[lang="zh-CN"] h1 .grad { white-space: nowrap; }
html[lang="zh-CN"] .section-head h2, html[lang="zh-CN"] .cta-band h2 { letter-spacing: 0; }