/* ===================== TOKENS ===================== */
:root {
  --bg: #0a0a0f;
  --bg-raised: #13131a;
  --bg-raised-2: #181820;
  --border: #23232c;
  --border-soft: #1c1c24;
  --text: #e9e9ee;
  --text-muted: #9a9aa5;
  --text-dim: #5a5a65;
  --accent: #c2b5ff;
  --accent-soft: rgba(194, 181, 255, 0.14);
  --bright: #ffffff;
  --warm: #ffd97a;
  --dim: #6a6a78;

  --maxw: 1080px;
  --radius: 20px;
  --radius-sm: 12px;

  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-cjk: "Noto Serif HK", "Inter", -apple-system, "PingFang HK", "Microsoft JhengHei", sans-serif;
}

/* ===================== RESET ===================== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-weight: 300;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
body[data-lang="zh"] { font-family: var(--font-cjk); letter-spacing: 0.01em; }
a { color: inherit; text-decoration: none; }
h1, h2, h3 { font-weight: 300; letter-spacing: -0.02em; line-height: 1.15; margin: 0; }
p { margin: 0; }
img, svg { display: block; }

/* ===================== STARFIELD ===================== */
#starfield {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
  pointer-events: none;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(120% 80% at 50% -10%, rgba(122, 109, 216, 0.16), transparent 60%),
    radial-gradient(100% 60% at 80% 110%, rgba(194, 181, 255, 0.07), transparent 55%);
  pointer-events: none;
}

/* ===================== NAV ===================== */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(20px, 5vw, 48px);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(10, 10, 15, 0.55);
  border-bottom: 1px solid transparent;
  transition: border-color 0.4s ease, background 0.4s ease;
}
.nav.scrolled {
  border-bottom-color: var(--border-soft);
  background: rgba(10, 10, 15, 0.82);
}
.brand { display: inline-flex; align-items: center; gap: 10px; }
.brand-mark {
  width: 30px; height: 30px;
  border-radius: 9px;
  object-fit: cover;
  border: 1px solid var(--border-soft);
  box-shadow: 0 0 18px rgba(194, 181, 255, 0.28);
}
.brand-name { font-size: 18px; font-weight: 400; letter-spacing: 0.02em; }
.nav-links { display: flex; gap: 30px; font-size: 14.5px; color: var(--text-muted); }
.nav-links a { transition: color 0.2s; }
.nav-links a:hover { color: var(--text); }
.nav-actions { display: flex; align-items: center; gap: 14px; }

.lang-toggle {
  font-family: inherit;
  font-size: 13.5px;
  color: var(--text-muted);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 7px 14px;
  cursor: pointer;
  transition: all 0.2s;
}
.lang-toggle:hover { color: var(--text); border-color: var(--accent); }
body[data-lang="en"] [data-zh-active] { display: none; }
body[data-lang="zh"] [data-en-active] { display: none; }

/* ===================== BUTTONS ===================== */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-family: inherit; font-weight: 400;
  background: var(--accent);
  color: #12101c;
  border-radius: 999px;
  padding: 12px 24px;
  transition: transform 0.2s, box-shadow 0.2s, filter 0.2s;
  box-shadow: 0 4px 24px rgba(194, 181, 255, 0.25);
}
.btn:hover { transform: translateY(-2px); filter: brightness(1.05); box-shadow: 0 8px 30px rgba(194, 181, 255, 0.35); }
.btn-small { padding: 9px 18px; font-size: 14px; }

/* ===================== LAYOUT ===================== */
main { display: block; }
.section { padding: clamp(72px, 11vw, 140px) clamp(20px, 5vw, 48px); position: relative; }
.section-inner { max-width: var(--maxw); margin: 0 auto; width: 100%; }
.section-inner.narrow { max-width: 720px; }
.section-inner.center { text-align: center; }
.section-head { max-width: 620px; margin-bottom: clamp(40px, 6vw, 64px); }

.kicker, .section-kicker {
  font-size: 13px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 400;
  margin-bottom: 22px;
}
.section-kicker { margin-bottom: 18px; }
.lead { color: var(--text-muted); font-size: clamp(16px, 2vw, 19px); line-height: 1.7; max-width: 640px; }
.center .lead { margin-left: auto; margin-right: auto; }

/* ===================== HERO ===================== */
.hero {
  min-height: 92vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: clamp(80px, 12vh, 160px) clamp(20px, 5vw, 48px) clamp(60px, 8vw, 100px);
  position: relative;
}
.hero-logo {
  width: clamp(72px, 12vw, 104px);
  height: auto;
  margin-bottom: clamp(20px, 3vw, 30px);
  border-radius: 24px;
  border: 1px solid var(--border-soft);
  box-shadow: 0 12px 55px rgba(122, 109, 216, 0.4);
}
.hero h1 {
  font-size: clamp(44px, 9vw, 92px);
  font-weight: 200;
  line-height: 1.02;
  margin-bottom: 28px;
  letter-spacing: -0.03em;
}
.hero h1 .line { display: block; }
.hero h1 .accent {
  background: linear-gradient(120deg, #fff 10%, var(--accent) 90%);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}
.hero-sub {
  color: var(--text-muted);
  font-size: clamp(16px, 2.2vw, 20px);
  max-width: 620px;
  line-height: 1.7;
  margin-bottom: 40px;
}
.hero-evidence {
  margin-top: 40px;
  font-size: 13.5px;
  color: var(--text-dim);
  max-width: 520px;
  line-height: 1.6;
}

/* ===================== STORE BADGES ===================== */
.store-badges { display: flex; gap: 14px; flex-wrap: wrap; justify-content: center; }
.store-badges.center { justify-content: center; margin-top: 8px; }
.store-badge {
  display: inline-flex; align-items: center; gap: 12px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 11px 20px;
  transition: border-color 0.2s, transform 0.2s, background 0.2s;
}
.store-badge:hover { border-color: var(--accent); transform: translateY(-2px); background: var(--bg-raised-2); }
.store-badge svg { width: 26px; height: 26px; fill: var(--text); flex-shrink: 0; }
.store-badge span { display: flex; flex-direction: column; align-items: flex-start; line-height: 1.15; }
.store-badge small { font-size: 10.5px; color: var(--text-muted); letter-spacing: 0.04em; }
.store-badge strong { font-size: 17px; font-weight: 500; }

/* ===================== PROBLEM ===================== */
.problem h2 { font-size: clamp(28px, 5vw, 46px); margin-bottom: 24px; }

/* ===================== STEPS ===================== */
.section-head h2, .split-text h2, .privacy h2, .cta h2 { font-size: clamp(28px, 5vw, 46px); }
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: clamp(20px, 3vw, 32px); }
.step {
  background: linear-gradient(180deg, var(--bg-raised) 0%, rgba(19,19,26,0.4) 100%);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  padding: clamp(28px, 3vw, 38px);
  transition: border-color 0.3s, transform 0.3s;
}
.step:hover { border-color: var(--border); transform: translateY(-4px); }
.step-num {
  font-size: 13px; letter-spacing: 0.12em; color: var(--accent);
  font-variant-numeric: tabular-nums; font-weight: 500;
}
.step h3 { font-size: 22px; margin: 18px 0 12px; font-weight: 400; }
.step p { color: var(--text-muted); font-size: 15.5px; line-height: 1.65; }

/* ===================== SHOWCASE / SPLIT ===================== */
.showcase { background: linear-gradient(180deg, transparent, rgba(19,19,26,0.35), transparent); }
.split { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: clamp(40px, 6vw, 80px); align-items: center; }
.split-text h2 { margin-bottom: 24px; }
.legend { list-style: none; padding: 0; margin: 32px 0 0; display: flex; flex-direction: column; gap: 14px; }
.legend li { display: flex; align-items: center; gap: 12px; color: var(--text-muted); font-size: 15px; }
.dot { width: 10px; height: 10px; border-radius: 50%; flex-shrink: 0; }
.dot.bright { background: var(--bright); box-shadow: 0 0 10px rgba(255,255,255,0.8); }
.dot.warm { background: var(--warm); box-shadow: 0 0 10px rgba(255,217,122,0.6); }
.dot.dim { background: var(--dim); }

/* ===================== PHONE MOCKUP ===================== */
.split-visual { display: flex; justify-content: center; }
.phone {
  width: min(300px, 78vw);
  aspect-ratio: 9 / 19;
  border-radius: 40px;
  padding: 12px;
  background: linear-gradient(160deg, #23232c, #101014);
  border: 1px solid #2c2c38;
  box-shadow: 0 30px 80px rgba(0,0,0,0.55), 0 0 0 1px rgba(194,181,255,0.06);
  position: relative;
}
.phone::before {
  content: ""; position: absolute; top: 18px; left: 50%; transform: translateX(-50%);
  width: 90px; height: 6px; border-radius: 999px; background: #2c2c38; z-index: 2;
}
.phone-screen {
  width: 100%; height: 100%; border-radius: 30px; overflow: hidden;
  background: radial-gradient(120% 90% at 50% 0%, #14121f, #05050a 70%);
  position: relative; padding: 44px 22px 26px; display: flex; flex-direction: column;
}
.phone-title {
  font-size: 15px; color: var(--text-muted); text-align: center; letter-spacing: 0.02em;
  font-weight: 400;
}
.sky-stars { position: absolute; inset: 60px 0 90px; }
.sky-stars .s {
  position: absolute; border-radius: 50%; background: #fff;
  animation: twinkle var(--tw, 3s) ease-in-out infinite alternate;
}
@keyframes twinkle { from { opacity: 0.35; } to { opacity: 1; } }
.sky-stat {
  margin-top: auto; text-align: center; display: flex; flex-direction: column; gap: 4px;
  color: var(--text-muted); font-size: 12.5px; line-height: 1.4; position: relative; z-index: 2;
}
.sky-stat .big {
  font-size: 34px; font-weight: 200; color: #fff; letter-spacing: -0.02em;
  text-shadow: 0 0 24px rgba(194,181,255,0.4);
}

/* ===================== SCIENCE ===================== */
.science { text-align: center; }
.stat-big { display: flex; flex-direction: column; gap: 8px; margin: 12px 0 34px; }
.stat-num {
  font-size: clamp(56px, 12vw, 104px); font-weight: 200; letter-spacing: -0.04em;
  background: linear-gradient(120deg, #fff, var(--accent));
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; color: transparent;
  line-height: 1;
}
.stat-label { color: var(--text-muted); font-size: clamp(15px, 2vw, 18px); letter-spacing: 0.02em; }
.citation { margin-top: 28px; color: var(--text-dim); font-size: 13px; }
.citation em { font-style: italic; }

/* ===================== PULL QUOTE ===================== */
.quote-section { padding-top: 0; }
.pull-quote {
  margin: 0; border: 0; padding: 0;
  font-size: clamp(22px, 3.6vw, 36px);
  font-weight: 200;
  line-height: 1.4;
  letter-spacing: -0.02em;
  color: var(--text);
  position: relative;
}
.pull-quote::before {
  content: "“"; display: block; font-size: 64px; color: var(--accent);
  opacity: 0.5; line-height: 0.6; margin-bottom: 18px;
}
body[data-lang="zh"] .pull-quote::before { content: "「"; }

/* ===================== PRIVACY CARDS ===================== */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: clamp(18px, 2.5vw, 28px); }
.card {
  background: var(--bg-raised);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  padding: clamp(26px, 3vw, 34px);
  transition: border-color 0.3s, transform 0.3s;
}
.card:hover { border-color: var(--border); transform: translateY(-4px); }
.card-icon {
  width: 46px; height: 46px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; background: var(--accent-soft); margin-bottom: 20px;
}
.card h3 { font-size: 18.5px; font-weight: 400; margin-bottom: 12px; }
.card p { color: var(--text-muted); font-size: 15px; line-height: 1.65; }

/* ===================== CTA ===================== */
.cta {
  background:
    radial-gradient(80% 120% at 50% 120%, rgba(122,109,216,0.22), transparent 60%);
}
.cta h2 { font-size: clamp(32px, 6vw, 56px); margin-bottom: 22px; }
.cta .lead { margin-bottom: 38px; }
.cta-foot {
  margin-top: 44px; color: var(--text-dim); font-size: 15px; letter-spacing: 0.04em; font-style: italic;
}

/* ===================== FOOTER ===================== */
.footer {
  border-top: 1px solid var(--border-soft);
  padding: clamp(48px, 6vw, 72px) clamp(20px, 5vw, 48px) 40px;
  background: rgba(6,6,10,0.6);
}
.footer-inner {
  max-width: var(--maxw); margin: 0 auto;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 32px;
  padding-bottom: 36px; border-bottom: 1px solid var(--border-soft);
}
.footer-tagline { color: var(--text-dim); font-size: 14px; margin-top: 12px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 24px; font-size: 14.5px; color: var(--text-muted); align-items: center; }
.footer-links a:hover { color: var(--text); }
.footer-crisis {
  max-width: var(--maxw); margin: 28px auto 0; color: var(--text-dim);
  font-size: 13px; line-height: 1.6;
}
.footer-legal {
  max-width: var(--maxw); margin: 24px auto 0; color: var(--text-dim);
  font-size: 13px; display: flex; gap: 10px; align-items: center; flex-wrap: wrap;
}
.footer-legal a:hover { color: var(--text-muted); }
.footer-legal .sep { opacity: 0.5; }

/* ===================== REVEAL ANIMATION ===================== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.8s cubic-bezier(0.22, 1, 0.36, 1), transform 0.8s cubic-bezier(0.22, 1, 0.36, 1);
}
.reveal.in { opacity: 1; transform: none; }

/* ===================== RESPONSIVE ===================== */
@media (max-width: 880px) {
  .nav-links { display: none; }
  .steps, .cards { grid-template-columns: 1fr; }
  .split { grid-template-columns: 1fr; gap: 48px; }
  .split-visual { order: -1; }
  .legend { flex-direction: row; flex-wrap: wrap; gap: 20px; }
}
@media (max-width: 480px) {
  .store-badge { padding: 10px 16px; }
  .nav-actions .btn-small { display: none; }
}

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