/* TTLive marketing design tokens.
   Structure/rhythm borrowed from the Notion marketing system (4px spacing base,
   8px rect buttons + 12px cards, 5-level elevation, tight negative-tracked
   display type, 1280 container, 96px section rhythm). Colors stay ours
   (Match Ops: dark hero band, volt-green primary, paper-gray surfaces). */

:root {
  /* color — unchanged brand palette */
  --bg: #f4f5f7;
  --surface: #eceef1;
  --card: #ffffff;
  --fg: #22252c;
  --muted: #6b7280;
  --stone: #9aa1ab;
  --primary: #3e7d1f;
  --primary-bright: #b5e841;
  --on-primary: #ffffff;
  --border: rgba(0, 0, 0, .1);
  --border-soft: rgba(0, 0, 0, .06);
  --dark-bg: #0d1017;
  --dark-fg: #e8eaf0;
  --dark-muted: #aab2c2;
  --red: #c0392b;

  /* spacing — 4px base */
  --sp-1: 4px;   --sp-2: 8px;   --sp-3: 12px;  --sp-4: 16px;
  --sp-5: 20px;  --sp-6: 24px;  --sp-7: 32px;  --sp-8: 40px;
  --sp-9: 48px;  --sp-10: 64px; --sp-11: 96px; --sp-12: 120px;

  /* radius — buttons are rectangles (8px), cards 12px, pills reserved for badges */
  --r-sm: 6px; --r-md: 8px; --r-lg: 12px; --r-xl: 16px; --r-full: 9999px;

  /* elevation */
  --e-1: 0 1px 2px rgba(15, 15, 15, .04);
  --e-2: 0 4px 12px rgba(15, 15, 15, .08);
  --e-3: 0 24px 48px -8px rgba(15, 15, 15, .28);   /* product mockup */
  --e-4: 0 16px 48px -8px rgba(15, 15, 15, .16);   /* modals */

  --container: 1280px;
  --gutter: 32px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, "Segoe UI", Roboto, Inter, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
/* height:auto is load-bearing — the width/height attributes are presentational
   hints, so without it an img whose CSS width is set keeps its attribute height
   and renders squashed. With it, the attributes still supply aspect-ratio (CLS
   stays at zero) but the box follows the real proportions. */
img, video { max-width: 100%; height: auto; display: block; }

.wrap { max-width: var(--container); margin: 0 auto; padding: 0 var(--gutter); }

/* ---------- type scale (tight leading + negative tracking on display) ---------- */
/* capped at 60px: the hero must leave room for the product visual — a bigger
   headline pushes the proof (levels, badges, bonus bars) below the fold, and
   the visual IS the argument */
.t-hero {
  font-size: clamp(32px, 4.6vw, 60px);
  line-height: 1.08;
  letter-spacing: -.02em;
  font-weight: 900;
}
.t-display { font-size: clamp(28px, 4.2vw, 52px); line-height: 1.1; letter-spacing: -.015em; font-weight: 900; }
.t-h2 { font-size: clamp(24px, 3.2vw, 36px); line-height: 1.2; letter-spacing: -.01em; font-weight: 900; }
.t-h3 { font-size: clamp(20px, 2.2vw, 26px); line-height: 1.25; letter-spacing: -.005em; font-weight: 800; }
.t-h5 { font-size: 17px; line-height: 1.4; font-weight: 700; }
.t-sub { font-size: 18px; line-height: 1.5; font-weight: 400; }
.t-body { font-size: 16px; line-height: 1.55; }
.t-sm { font-size: 14px; line-height: 1.5; }
.t-cap { font-size: 13px; line-height: 1.4; }
.t-micro {
  font-size: 11px; font-weight: 700; line-height: 1.4;
  letter-spacing: .1em; text-transform: uppercase;
}

/* CJK: the display scale above is tuned for Latin. Chinese glyphs are denser
   and squarer — negative tracking and 1.05 leading make them look cramped and
   the same point size overwhelms the band. Drop a tier and relax. */
html[lang="zh-CN"] .t-hero { font-size: clamp(28px, 4vw, 50px); line-height: 1.28; letter-spacing: 0; }
html[lang="zh-CN"] .t-display { font-size: clamp(24px, 3.2vw, 38px); line-height: 1.3; letter-spacing: 0; }
html[lang="zh-CN"] .t-h2 { font-size: clamp(22px, 2.8vw, 30px); line-height: 1.35; letter-spacing: 0; }
html[lang="zh-CN"] .t-h3 { font-size: clamp(19px, 2vw, 23px); line-height: 1.4; letter-spacing: 0; }

/* ---------- buttons (8px rectangles) ---------- */
.btn {
  display: inline-block;
  padding: 10px 18px;
  border-radius: var(--r-md);
  font-weight: 700;
  font-size: 14px;
  line-height: 1.3;
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--card);
  transition: filter .15s ease, border-color .15s ease;
}
.btn:hover { border-color: var(--primary); }
.btn.primary { background: var(--primary); color: var(--on-primary); border-color: var(--primary); }
.btn.primary:hover { filter: brightness(1.12); }
.btn.ghost { background: transparent; }
.btn.lg { padding: 13px 26px; font-size: 15px; }
/* on the dark band the volt variant carries the CTA */
.on-dark .btn.primary { background: var(--primary-bright); color: #16240a; border-color: var(--primary-bright); }
.on-dark .btn.ghost { color: var(--dark-fg); border-color: rgba(255, 255, 255, .25); }

/* ---------- surfaces ---------- */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: var(--sp-6);
}
.badge {
  display: inline-block;
  border-radius: var(--r-full);
  padding: 4px 10px;
  font-size: 12px;
  font-weight: 700;
  background: var(--primary);
  color: var(--on-primary);
}

section { padding: var(--sp-11) 0 0; }
h2.sec { text-align: center; margin-bottom: var(--sp-3); }
p.lede { text-align: center; color: var(--muted); max-width: 660px; margin: 0 auto var(--sp-8); font-size: 17px; }

/* ---------- legal / doc pages ---------- */
.doc { max-width: 760px; margin: 0 auto; padding: var(--sp-8) var(--sp-6) var(--sp-11); }
.doc h1 { font-size: 30px; font-weight: 900; letter-spacing: -.01em; margin-bottom: var(--sp-2); }
.doc h2 { font-size: 18px; font-weight: 800; margin-top: var(--sp-7); margin-bottom: var(--sp-2); }
.doc p, .doc li { font-size: 15px; color: #4b5563; margin-bottom: var(--sp-2); }
.doc a { color: var(--primary); font-weight: 600; }
.doc .back { display: inline-block; margin-bottom: var(--sp-6); font-size: 14px; font-weight: 700; color: var(--primary); }

@media (max-width: 820px) {
  :root { --gutter: 20px; }
}