/* ============================================================
   Cuspix Capital — Editorial Black
   Inspired by Pantera Capital · institutional digital asset firm
   ============================================================ */

:root {
  --bg: #0A0A0A;
  --bg-2: #111111;
  --bg-3: #161616;
  --ink: #F2F2F2;
  --ink-soft: #E5E5E5;
  --ink-dim: #9A9A9A;
  --ink-mute: #6B6B6B;
  --ink-faint: #3F3F3F;
  --hairline: rgba(255, 255, 255, 0.08);
  --hairline-strong: rgba(255, 255, 255, 0.18);
  --accent: #00E0FF;

  --serif: 'Fraunces', 'Source Serif 4', 'Times New Roman', Georgia, serif;
  --sans:  'Inter', 'Helvetica Neue', Arial, sans-serif;
  --mono:  'JetBrains Mono', 'SF Mono', 'Menlo', monospace;
  --cn:    'PingFang SC', 'Microsoft YaHei', 'Source Han Sans SC', 'Noto Sans CJK SC', sans-serif;

  --maxw: 1240px;
  --pad-x: clamp(24px, 5vw, 64px);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  font-weight: 400;
  background: var(--bg);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  line-height: 1.55;
  overflow-x: hidden;
  font-size: 16px;
}
html[data-lang="zh"] body { font-family: var(--cn); }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: 0; background: none; color: inherit; }

::selection { background: var(--accent); color: var(--bg); }

.rule {
  height: 1px; width: 100%;
  background: var(--hairline);
  margin: 0;
}
.rule-top { margin-bottom: 56px; }

/* ============================================================
   Header
   ============================================================ */
.hd {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  padding: 22px var(--pad-x);
  background: rgba(10,10,10,0.78);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--hairline);
}
.hd-brand { display: flex; align-items: center; gap: 14px; color: var(--ink); }
.hd-mark { width: 38px; height: 22px; color: var(--ink); }
.hd-words { display: flex; flex-direction: column; line-height: 1; gap: 4px; }
.hd-en { font-family: var(--sans); font-weight: 700; font-size: 13px; letter-spacing: 3px; }
.hd-cn { font-family: var(--cn); font-weight: 500; font-size: 10px; letter-spacing: 4px; color: var(--ink-dim); }

.hd-nav { display: flex; gap: 40px; }
.hd-nav a {
  font-size: 12px; font-weight: 500; letter-spacing: 2px;
  text-transform: uppercase; color: var(--ink-dim);
  transition: color .2s;
  position: relative; padding: 4px 0;
}
.hd-nav a:hover { color: var(--ink); }
.hd-nav a::after {
  content: ''; position: absolute; left: 0; right: 0; bottom: -2px;
  height: 1px; background: var(--accent);
  transform: scaleX(0); transform-origin: left;
  transition: transform .25s ease;
}
.hd-nav a:hover::after { transform: scaleX(1); }

.hd-lang { display: flex; align-items: center; gap: 8px; font-size: 12px; }
.hd-lang button {
  padding: 4px 6px; color: var(--ink-mute);
  letter-spacing: 1px; font-weight: 500; transition: color .2s;
}
.hd-lang button.active { color: var(--ink); }
.hd-lang button:hover { color: var(--accent); }
.hd-sep { color: var(--ink-faint); }

/* ============================================================
   Hero
   ============================================================ */
.hero {
  padding: 96px var(--pad-x) 140px;
  max-width: var(--maxw); margin: 0 auto;
  position: relative;
}
.hero-meta {
  display: flex; justify-content: space-between; align-items: center;
  font-size: 11px; letter-spacing: 3px; text-transform: uppercase;
  color: var(--ink-mute); font-weight: 500;
  margin-bottom: 80px;
  flex-wrap: wrap; gap: 12px;
}
.hero-est { color: var(--ink-faint); font-family: var(--mono); letter-spacing: 2px; }

.hero-title {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(56px, 9vw, 144px);
  line-height: 0.94;
  letter-spacing: -0.025em;
  color: var(--ink);
  font-variation-settings: "opsz" 144;
}
.hero-title .line { display: block; }
.hero-title .line.accent {
  font-style: italic;
  font-weight: 300;
  color: var(--ink-soft);
}
html[data-lang="zh"] .hero-title {
  font-family: var(--cn); font-weight: 600;
  font-size: clamp(48px, 8vw, 120px); letter-spacing: 0.02em; line-height: 1.05;
}
html[data-lang="zh"] .hero-title .line.accent { font-style: normal; font-weight: 400; color: var(--ink-soft); }

.hero-sub {
  margin-top: 48px;
  max-width: 640px;
  font-size: 17px;
  line-height: 1.7;
  color: var(--ink-dim);
  font-weight: 400;
}

.hero-actions {
  margin-top: 56px;
  display: flex; gap: 48px; flex-wrap: wrap;
}

.link-arrow {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 13px; font-weight: 500; letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--ink); padding: 10px 0;
  border-bottom: 1px solid var(--hairline-strong);
  transition: all .25s;
}
.link-arrow svg { transition: transform .25s; }
.link-arrow:hover { border-color: var(--accent); color: var(--accent); }
.link-arrow:hover svg { transform: translateX(4px); }

/* ============================================================
   Stats strip
   ============================================================ */
.stats {
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  padding: 48px var(--pad-x);
  background: var(--bg);
}
.stats-grid {
  max-width: var(--maxw); margin: 0 auto;
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 0;
}
.stat {
  padding: 0 32px;
  border-left: 1px solid var(--hairline);
}
.stat:first-child { border-left: 0; padding-left: 0; }
.stat-num {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(48px, 5.6vw, 76px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
  font-variation-settings: "opsz" 96;
}
.stat-unit {
  font-family: var(--serif);
  font-size: 0.45em;
  vertical-align: top;
  margin-left: 4px;
  color: var(--ink-dim);
  font-style: italic;
  font-weight: 300;
}
.stat-sep { color: var(--ink-dim); font-weight: 300; }
.stat-label {
  margin-top: 16px;
  font-size: 11px; letter-spacing: 2.5px; text-transform: uppercase;
  color: var(--ink-mute); font-weight: 500;
  line-height: 1.5;
}

/* ============================================================
   Sections
   ============================================================ */
.sec {
  max-width: var(--maxw); margin: 0 auto;
  padding: 140px var(--pad-x);
}
.sec-head { display: grid; grid-template-columns: 200px 1fr; gap: 64px; margin-bottom: 80px; align-items: start; }
.kicker {
  font-size: 11px; letter-spacing: 3px; text-transform: uppercase;
  color: var(--accent); font-weight: 600;
  font-family: var(--mono);
  padding-top: 12px;
}
.sec-title {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(34px, 4.6vw, 64px);
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--ink);
  font-variation-settings: "opsz" 96;
}
.sec-title > span { display: block; }
.sec-title-em {
  font-style: italic; font-weight: 300; color: var(--ink-dim);
  margin-top: 6px;
}
html[data-lang="zh"] .sec-title { font-family: var(--cn); font-weight: 500; font-size: clamp(30px, 4vw, 52px); letter-spacing: 0.02em; line-height: 1.2; }
html[data-lang="zh"] .sec-title-em { font-style: normal; font-weight: 400; color: var(--ink-dim); }

/* ============ Argument grid (3-col horizontal insights) ============ */
.argument-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 56px;
  border-top: 1px solid var(--hairline);
  padding-top: 64px;
}
.argument { display: flex; flex-direction: column; }
.argument-num {
  font-family: var(--mono); font-size: 12px; letter-spacing: 2px;
  color: var(--accent); margin-bottom: 28px; font-weight: 500;
}
.argument h3 {
  font-family: var(--serif); font-weight: 400;
  font-size: 26px; letter-spacing: -0.01em; line-height: 1.2;
  color: var(--ink); margin-bottom: 18px;
}
html[data-lang="zh"] .argument h3 { font-family: var(--cn); font-weight: 500; font-size: 22px; line-height: 1.4; }
.argument p {
  font-size: 15px; line-height: 1.75; color: var(--ink-dim);
  font-weight: 400;
}

/* ============ Closing line ============ */
.sec-closing { padding: 160px var(--pad-x); }
.closing-inner { max-width: var(--maxw); margin: 0 auto; }
.closing-headline {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(40px, 6vw, 88px);
  line-height: 1.05; letter-spacing: -0.02em;
  color: var(--ink);
  font-variation-settings: "opsz" 96;
}
.closing-headline > span { display: block; }
html[data-lang="zh"] .closing-headline { font-family: var(--cn); font-weight: 500; font-size: clamp(36px, 5vw, 72px); letter-spacing: 0.02em; line-height: 1.2; }

/* ============================================================
   Approach (4 pillars)
   ============================================================ */
.pillars {
  display: grid; grid-template-columns: repeat(2, 1fr);
  border-top: 1px solid var(--hairline);
  border-left: 1px solid var(--hairline);
}
.pillar {
  padding: 56px 48px;
  border-right: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  position: relative;
  transition: background .3s ease;
}
.pillar:hover { background: rgba(255,255,255,0.02); }
.pillar-num {
  font-family: var(--mono);
  font-size: 12px; letter-spacing: 2px;
  color: var(--accent); font-weight: 500;
  margin-bottom: 32px;
}
.pillar h3 {
  font-family: var(--serif); font-weight: 400;
  font-size: 30px; letter-spacing: -0.01em; line-height: 1.15;
  color: var(--ink); margin-bottom: 20px;
}
html[data-lang="zh"] .pillar h3 { font-family: var(--cn); font-weight: 500; font-size: 26px; }
.pillar p {
  font-size: 15px; line-height: 1.7;
  color: var(--ink-dim); max-width: 460px;
}

/* ============================================================
   Engine
   ============================================================ */
.engine-grid {
  display: grid; grid-template-columns: 1.1fr 1fr; gap: 96px;
  align-items: start;
}
.engine-name {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(72px, 10vw, 144px);
  line-height: 0.95; letter-spacing: -0.04em;
  color: var(--ink);
  margin-top: 16px;
  font-variation-settings: "opsz" 144;
}
.tm { font-size: 0.18em; vertical-align: super; color: var(--accent); margin-left: 6px; }
.engine-tag {
  font-family: var(--serif); font-style: italic; font-weight: 300;
  font-size: 22px; line-height: 1.5; color: var(--ink-dim);
  margin-top: 24px;
  max-width: 480px;
}
html[data-lang="zh"] .engine-tag { font-family: var(--cn); font-style: normal; }

.curve-art {
  margin-top: 64px;
  background: var(--bg-2);
  border: 1px solid var(--hairline);
  padding: 24px;
  border-radius: 2px;
}
.curve-art svg { width: 100%; height: auto; display: block; }

.engine-right {
  display: flex; flex-direction: column;
  gap: 0;
  border-top: 1px solid var(--hairline);
}
.engine-feat {
  padding: 36px 0;
  border-bottom: 1px solid var(--hairline);
  display: grid; grid-template-columns: 60px 1fr; gap: 24px;
  align-items: start;
}
.engine-feat-num {
  font-family: var(--mono); font-size: 12px; letter-spacing: 2px;
  color: var(--accent); padding-top: 6px;
}
.engine-feat h4 {
  font-family: var(--serif); font-weight: 400;
  font-size: 22px; letter-spacing: -0.005em;
  color: var(--ink); margin-bottom: 10px;
}
html[data-lang="zh"] .engine-feat h4 { font-family: var(--cn); font-weight: 500; font-size: 19px; }
.engine-feat p {
  font-size: 14px; line-height: 1.7; color: var(--ink-dim);
}

/* ============================================================
   Contact
   ============================================================ */
.sec-contact { padding-top: 140px; padding-bottom: 140px; }
.contact-pull { max-width: 720px; margin-bottom: 72px; }
.contact-title {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(40px, 5.6vw, 80px);
  line-height: 1.05; letter-spacing: -0.02em;
  margin-top: 24px;
  font-variation-settings: "opsz" 96;
}
.contact-title > span { display: block; }
html[data-lang="zh"] .contact-title { font-family: var(--cn); font-weight: 500; font-size: clamp(34px, 4.6vw, 64px); letter-spacing: 0.02em; }
.contact-sub {
  margin-top: 24px;
  font-size: 17px; color: var(--ink-dim); max-width: 560px;
}

.contact-meta {
  border-top: 1px solid var(--hairline);
}
.meta-row {
  display: grid; grid-template-columns: 200px 1fr;
  align-items: baseline; padding: 28px 0;
  border-bottom: 1px solid var(--hairline);
  transition: padding .25s ease;
}
a.meta-row:hover { padding-left: 16px; }
a.meta-row:hover .meta-value { color: var(--accent); }
.meta-label {
  font-size: 11px; letter-spacing: 3px; text-transform: uppercase;
  color: var(--ink-mute); font-weight: 500;
}
.meta-value {
  font-family: var(--mono);
  font-size: 18px; color: var(--ink); font-weight: 400;
  letter-spacing: 0.02em;
  transition: color .25s;
}

/* ============================================================
   Footer
   ============================================================ */
.ft {
  border-top: 1px solid var(--hairline);
  padding: 56px var(--pad-x) 40px;
  background: #060606;
}
.ft-top {
  max-width: var(--maxw); margin: 0 auto;
  display: flex; justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: 16px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--hairline);
}
.ft-brand { display: flex; gap: 18px; align-items: baseline; }
.ft-en { font-size: 12px; letter-spacing: 3px; font-weight: 700; color: var(--ink); }
.ft-cn { font-family: var(--cn); font-size: 11px; letter-spacing: 3px; color: var(--ink-dim); }
.ft-tag {
  font-family: var(--serif); font-style: italic; font-weight: 300;
  font-size: 16px; color: var(--ink-dim);
}
html[data-lang="zh"] .ft-tag { font-family: var(--cn); font-style: normal; }

.ft-disclaimer {
  max-width: var(--maxw); margin: 32px auto 0;
  font-size: 11px; line-height: 1.7;
  color: var(--ink-mute);
}
.ft-bottom {
  max-width: var(--maxw); margin: 24px auto 0;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px;
  font-size: 11px; color: var(--ink-faint); letter-spacing: 1px;
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 1000px) {
  .hd-nav { display: none; }
  .sec-head { grid-template-columns: 1fr; gap: 32px; }
  .engine-grid { grid-template-columns: 1fr; gap: 64px; }
  .pillars { grid-template-columns: 1fr; }
  .pillar { padding: 40px 32px; }
  .argument-grid { grid-template-columns: 1fr; gap: 40px; padding-top: 48px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 32px 0; }
  .stat { border-left: 0; padding: 0 16px; }
  .sec { padding: 100px var(--pad-x); }
  .sec-closing { padding: 100px var(--pad-x); }
  .hero { padding: 64px var(--pad-x) 100px; }
}
@media (max-width: 600px) {
  .hd-brand .hd-cn { display: none; }
  .hero-actions { gap: 24px; flex-direction: column; align-items: flex-start; }
  .stats-grid { grid-template-columns: 1fr; gap: 32px; }
  .stat { padding: 0; }
  .stat:not(:first-child) { padding-top: 32px; border-top: 1px solid var(--hairline); }
  .meta-row { grid-template-columns: 100px 1fr; }
}