:root {
  color-scheme: dark;
  --bg: #0f0f0f;
  --bg-elevated: #1a1a1a;
  --bg-card: #161616;
  --ink: #ffffff;
  --ink-soft: rgba(255, 255, 255, 0.7);
  --muted: rgba(255, 255, 255, 0.4);
  --muted-more: rgba(255, 255, 255, 0.25);
  --line: rgba(255, 255, 255, 0.06);
  --line-hover: rgba(255, 255, 255, 0.12);
  --brand: #f97316;
  --brand-soft: rgba(249, 115, 22, 0.1);
  --brand-glow: rgba(249, 115, 22, 0.15);
  --shadow: 0 0 0 1px rgba(255, 255, 255, 0.03), 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-hover: 0 0 0 1px rgba(249, 115, 22, 0.2), 0 8px 32px rgba(249, 115, 22, 0.08);
  --radius: 16px;
  --radius-sm: 8px;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
  background: var(--bg);
}

body {
  min-height: 100vh;
  color: var(--ink);
  background: var(--bg);
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; }
button { font: inherit; border: 0; color: inherit; background: none; cursor: pointer; }

a:focus-visible, button:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
}

/* ===== HEADER ===== */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  padding: 0 24px;
  max-width: 1200px;
  margin: 0 auto;
}

.site-header::before {
  position: absolute;
  inset: 8px -16px;
  z-index: -1;
  content: "";
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(20px) saturate(1.2);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.brand-mark {
  display: block;
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.site-nav a {
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  transition: all 0.2s ease;
}

.site-nav a:hover {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.05);
}

.site-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.lang-toggle {
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.05);
  transition: all 0.2s ease;
}

.lang-toggle:hover {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.06);
}

.header-action {
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  color: #000;
  background: var(--brand);
  transition: all 0.2s ease;
}

.header-action:hover {
  opacity: 0.9;
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(249, 115, 22, 0.3);
}

/* ===== HERO ===== */
.hero {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 100svh;
  padding: 120px 24px 80px;
  overflow: hidden;
}

.ambient-canvas {
  position: absolute;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  opacity: 0.6;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 900px;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--brand);
  background: rgba(249, 115, 22, 0.08);
  border: 1px solid rgba(249, 115, 22, 0.15);
  margin-bottom: 32px;
}

.hero-eyebrow::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.hero h1 {
  font-size: clamp(4rem, 12vw, 10rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 0.9;
  margin-bottom: 24px;
  background: linear-gradient(180deg, #fff 0%, rgba(255,255,255,0.7) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-slogan {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
  font-weight: 500;
  color: var(--ink-soft);
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.hero-copy {
  font-size: clamp(1rem, 1.5vw, 1.25rem);
  color: var(--muted);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  transition: all 0.2s ease;
}

.button:hover { transform: translateY(-1px); }

.button-primary {
  background: var(--brand);
  color: #000;
  box-shadow: 0 4px 24px rgba(249, 115, 22, 0.25);
}

.button-primary:hover {
  box-shadow: 0 8px 32px rgba(249, 115, 22, 0.35);
}

.button-secondary {
  background: rgba(255, 255, 255, 0.05);
  color: var(--ink);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.button-secondary:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
}

/* ===== SIGNAL STRIP ===== */
.signal-strip {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 1px;
  max-width: 1200px;
  margin: 0 auto 160px;
  padding: 0 24px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: var(--line);
  border: 1px solid var(--line);
}

.signal-strip div {
  padding: 20px 16px;
  background: rgba(255, 255, 255, 0.02);
  transition: background 0.3s ease;
}

.signal-strip div:hover {
  background: rgba(249, 115, 22, 0.03);
}

.signal-strip span {
  display: block;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted-more);
  margin-bottom: 6px;
}

.signal-strip strong {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink-soft);
}

/* ===== SECTIONS ===== */
.product-band,
.principle-grid,
.closing-band {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.product-band { margin-bottom: 160px; }
.principle-grid { margin-bottom: 160px; }

.section-header {
  margin-bottom: 80px;
  max-width: 720px;
}

.section-eyebrow {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--brand);
  margin-bottom: 16px;
}

.section-header h2 {
  font-size: clamp(2.5rem, 6vw, 5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1;
  margin-bottom: 20px;
  background: linear-gradient(180deg, #fff 0%, rgba(255,255,255,0.8) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-header p {
  font-size: 18px;
  color: var(--muted);
  line-height: 1.6;
  max-width: 560px;
}

/* ===== PRODUCT CARDS ===== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.product-card {
  position: relative;
  padding: 32px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  overflow: hidden;
}

.product-card::before {
  position: absolute;
  inset: 0;
  content: "";
  background: radial-gradient(600px circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(249, 115, 22, 0.06), transparent 40%);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

.product-card:hover::before {
  opacity: 1;
}

.product-card:hover {
  border-color: var(--line-hover);
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.product-card:nth-child(4),
.product-card:nth-child(5) {
  grid-column: span 1;
}

.product-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
  margin-bottom: 24px;
  position: relative;
}

.product-card > span {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted-more);
  margin-bottom: 8px;
  display: block;
}

.product-card h3 {
  font-size: 24px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.product-card p {
  font-size: 15px;
  color: var(--muted);
  line-height: 1.6;
  margin-bottom: 20px;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.tag-row span {
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 500;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.06);
}

/* Product icon colors */
.product-card-gout .product-icon { background: linear-gradient(135deg, rgba(249, 115, 22, 0.1), rgba(249, 115, 22, 0.05)); border-color: rgba(249, 115, 22, 0.15); }
.product-card-invest .product-icon { background: linear-gradient(135deg, rgba(251, 191, 36, 0.1), rgba(251, 191, 36, 0.05)); border-color: rgba(251, 191, 36, 0.15); }
.product-card-study .product-icon { background: linear-gradient(135deg, rgba(52, 211, 153, 0.1), rgba(52, 211, 153, 0.05)); border-color: rgba(52, 211, 153, 0.15); }
.product-card-run .product-icon { background: linear-gradient(135deg, rgba(96, 165, 250, 0.1), rgba(96, 165, 250, 0.05)); border-color: rgba(96, 165, 250, 0.15); }
.product-card-eval .product-icon { background: linear-gradient(135deg, rgba(167, 139, 250, 0.1), rgba(167, 139, 250, 0.05)); border-color: rgba(167, 139, 250, 0.15); }

/* Product icon mini illustrations */
.product-icon::before,
.product-icon::after {
  position: absolute;
  content: "";
}

/* Gout Hero - pill */
.product-card-gout .product-icon::before {
  left: 12px;
  top: 10px;
  width: 16px;
  height: 20px;
  border: 2px solid rgba(249, 115, 22, 0.7);
  border-radius: 999px 999px 10px 10px;
  transform: rotate(25deg);
}

/* Invest OS - chart line + arrow */
.product-card-invest .product-icon::before {
  left: 10px;
  top: 22px;
  width: 20px;
  height: 2px;
  background: rgba(251, 191, 36, 0.7);
  transform: rotate(-30deg);
}
.product-card-invest .product-icon::after {
  right: 10px;
  top: 12px;
  width: 8px;
  height: 8px;
  border-top: 2px solid rgba(251, 191, 36, 0.7);
  border-right: 2px solid rgba(251, 191, 36, 0.7);
}

/* Study Master - book */
.product-card-study .product-icon::before {
  left: 10px;
  top: 12px;
  width: 20px;
  height: 16px;
  border: 2px solid rgba(52, 211, 153, 0.7);
  border-radius: 2px;
}
.product-card-study .product-icon::after {
  left: 20px;
  top: 12px;
  width: 2px;
  height: 16px;
  background: rgba(52, 211, 153, 0.7);
}

/* Run Hero - running figure */
.product-card-run .product-icon::before {
  left: 16px;
  top: 8px;
  width: 10px;
  height: 24px;
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(96, 165, 250, 0.6), rgba(59, 130, 246, 0.6));
  transform: skewX(-15deg);
}

/* Eval OS - checkbox */
.product-card-eval .product-icon::before {
  left: 10px;
  top: 10px;
  width: 20px;
  height: 20px;
  border: 2px solid rgba(167, 139, 250, 0.7);
  border-radius: 6px;
}
.product-card-eval .product-icon::after {
  left: 16px;
  top: 16px;
  width: 8px;
  height: 4px;
  border-left: 2px solid rgba(167, 139, 250, 0.7);
  border-bottom: 2px solid rgba(167, 139, 250, 0.7);
  transform: rotate(-45deg);
}

/* ===== PRINCIPLES ===== */
.principle-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.principle-card {
  padding: 32px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.principle-card:hover {
  border-color: var(--line-hover);
  transform: translateY(-2px);
}

.principle-card > span {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted-more);
  margin-bottom: 16px;
  display: block;
}

.principle-card h3 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
  line-height: 1.2;
}

.principle-card p {
  font-size: 15px;
  color: var(--muted);
  line-height: 1.6;
}

/* ===== CLOSING ===== */
.closing-band {
  text-align: center;
  padding: 160px 24px;
  border-top: 1px solid var(--line);
}

.closing-band .section-eyebrow {
  margin-bottom: 24px;
}

.closing-band h2 {
  font-size: clamp(2.5rem, 6vw, 5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1;
  margin-bottom: 40px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  background: linear-gradient(180deg, #fff 0%, rgba(255,255,255,0.8) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* ===== FOOTER ===== */
.site-footer {
  max-width: 1200px;
  margin: 0 auto;
  padding: 80px 24px 40px;
  border-top: 1px solid var(--line);
}

.footer-top {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 80px;
  margin-bottom: 60px;
}

.footer-brand p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
  margin-top: 12px;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.footer-links h4 {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted-more);
  margin-bottom: 16px;
}

.footer-links a {
  display: block;
  font-size: 14px;
  color: var(--muted);
  padding: 4px 0;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--brand);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--muted-more);
}

.footer-bottom a {
  color: var(--muted);
  margin-left: 20px;
  transition: color 0.2s ease;
}

.footer-bottom a:hover {
  color: var(--brand);
}

/* ===== REVEAL ANIMATION ===== */
[data-reveal] {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

[data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 900px) {
  .site-nav { display: none; }
  .product-grid,
  .principle-grid,
  .footer-top,
  .footer-links {
    grid-template-columns: 1fr;
  }
  .footer-top { gap: 40px; }
  .signal-strip { grid-template-columns: repeat(2, 1fr); }
  .hero h1 { font-size: clamp(3rem, 12vw, 5rem); }
}

@media (max-width: 620px) {
  .site-header { padding: 0 16px; }
  .site-header::before { inset: 8px -8px; }
  .header-action { display: none; }
  .hero { padding: 100px 16px 60px; }
  .hero-actions { width: 100%; }
  .button { width: 100%; }
  .section-header h2,
  .closing-band h2 {
    font-size: clamp(2rem, 8vw, 3rem);
  }
  .product-card,
  .principle-card {
    padding: 24px;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 12px;
    align-items: flex-start;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}