:root {
  --bg: #0a0a0c;
  --bg-elevated: #141418;
  --bg-card: #1a1a20;
  --fg: #e8e6e1;
  --fg-muted: #8a8780;
  --fg-dim: #5a5850;
  --accent: #e8a838;
  --accent-glow: rgba(232, 168, 56, 0.15);
  --accent-subtle: #2a2418;
  --border: #2a2a30;
  --radius: 12px;
  --radius-sm: 8px;
  --font-display: 'Space Grotesk', sans-serif;
  --font-body: 'DM Sans', sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* Hero */
.hero {
  min-height: 90vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 24px;
  position: relative;
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, var(--accent-glow) 0%, transparent 70%),
    var(--bg);
}

.hero-inner {
  max-width: 820px;
  text-align: center;
}

.hero-badge {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-subtle);
  border: 1px solid rgba(232, 168, 56, 0.2);
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 32px;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}

.hero h1 .strike {
  text-decoration: line-through;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 3px;
}

.lede {
  font-size: 1.15rem;
  color: var(--fg-muted);
  max-width: 600px;
  margin: 0 auto 48px;
  line-height: 1.7;
}

.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 32px;
  padding: 32px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.stat { text-align: center; }

.stat-num {
  display: block;
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.2;
}

.stat-label {
  display: block;
  font-size: 0.8rem;
  color: var(--fg-dim);
  line-height: 1.4;
  margin-top: 4px;
}

.stat-divider {
  width: 1px;
  height: 48px;
  background: var(--border);
}

/* Problem section */
.problem {
  padding: 100px 24px;
}

.problem-inner {
  max-width: 1000px;
  margin: 0 auto;
}

.section-label {
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 48px;
}

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

.problem-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  transition: border-color 0.2s;
}

.problem-card:hover {
  border-color: var(--accent);
}

.problem-icon {
  font-size: 2rem;
  margin-bottom: 16px;
}

.problem-card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 12px;
  line-height: 1.3;
}

.problem-card p {
  color: var(--fg-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* Features */
.features {
  padding: 100px 24px;
  background: var(--bg-elevated);
}

.features-inner {
  max-width: 1000px;
  margin: 0 auto;
}

.feature-row {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}

.feature-row:nth-child(odd) {
  grid-template-columns: 1fr 1.4fr;
}

.feature-block {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px;
}

.feature-tag {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-subtle);
  padding: 4px 10px;
  border-radius: 4px;
  margin-bottom: 16px;
}

.feature-block h3 {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.feature-block p {
  color: var(--fg-muted);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* Math section */
.math {
  padding: 100px 24px;
}

.math-inner {
  max-width: 700px;
  margin: 0 auto;
}

.math-content {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 48px;
}

.math-equation {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 32px;
}

.math-line {
  display: flex;
  align-items: baseline;
  gap: 16px;
}

.math-val {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--fg);
  min-width: 120px;
}

.math-result .math-val {
  color: var(--accent);
  font-size: 2.4rem;
}

.math-desc {
  color: var(--fg-muted);
  font-size: 1rem;
}

.math-operator {
  font-family: var(--font-display);
  font-size: 1.4rem;
  color: var(--fg-dim);
  padding-left: 40px;
}

.math-kicker {
  color: var(--fg-muted);
  font-size: 1rem;
  border-top: 1px solid var(--border);
  padding-top: 24px;
  font-style: italic;
}

/* Closing */
.closing {
  padding: 100px 24px;
  background: var(--bg-elevated);
  text-align: center;
}

.closing-inner {
  max-width: 700px;
  margin: 0 auto;
}

.closing h2 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}

.closing p {
  color: var(--fg-muted);
  font-size: 1.05rem;
  line-height: 1.7;
  margin-bottom: 40px;
}

.closing-trades {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.closing-trades span {
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--fg-muted);
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 8px 18px;
  border-radius: 100px;
  transition: all 0.2s;
}

.closing-trades span:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* Footer */
.site-footer {
  padding: 60px 24px;
  text-align: center;
  border-top: 1px solid var(--border);
}

.footer-inner {
  max-width: 600px;
  margin: 0 auto;
}

.footer-brand {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--fg);
  margin-bottom: 8px;
}

.footer-tagline {
  color: var(--fg-dim);
  font-size: 0.9rem;
  margin-bottom: 24px;
}

.footer-copy {
  color: var(--fg-dim);
  font-size: 0.8rem;
}

/* Responsive */
@media (max-width: 768px) {
  .hero { min-height: auto; padding: 60px 20px 48px; }
  .hero-stats { flex-direction: column; gap: 24px; }
  .stat-divider { width: 48px; height: 1px; }
  .problem-grid { grid-template-columns: 1fr; }
  .feature-row,
  .feature-row:nth-child(odd) { grid-template-columns: 1fr; }
  .math-content { padding: 32px 24px; }
  .math-line { flex-direction: column; gap: 4px; }
  .math-val { min-width: auto; }
  .math-operator { padding-left: 0; }
  .problem, .features, .math, .closing { padding: 64px 20px; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.8rem; }
  .closing h2 { font-size: 1.5rem; }
}