:root {
  --bg: #0a0a0f;
  --bg-elevated: #12121a;
  --bg-card: #1a1a26;
  --fg: #e8e6e3;
  --fg-muted: #8a8899;
  --accent: #f5a623;
  --accent-glow: rgba(245, 166, 35, 0.15);
  --accent-dim: #c4841c;
  --gradient-start: #f5a623;
  --gradient-end: #e8532e;
  --border: rgba(255,255,255,0.06);
  --radius: 16px;
  --font-heading: '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);
  line-height: 1.7;
  font-size: 17px;
  overflow-x: hidden;
}

/* ── NAV ── */
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1100px;
  margin: 0 auto;
  padding: 28px 24px;
}

.nav-logo {
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.5px;
  color: var(--fg);
}

.nav-logo span {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-tag {
  font-size: 13px;
  color: var(--fg-muted);
  border: 1px solid var(--border);
  padding: 6px 14px;
  border-radius: 100px;
}

/* ── HERO ── */
.hero {
  max-width: 900px;
  margin: 0 auto;
  padding: 80px 24px 100px;
  text-align: left;
}

.hero-eyebrow {
  font-family: var(--font-heading);
  font-size: 14px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--accent);
  margin-bottom: 24px;
}

.hero h1 {
  font-family: var(--font-heading);
  font-size: clamp(42px, 7vw, 76px);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -2px;
  margin-bottom: 28px;
  color: var(--fg);
}

.hero h1 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: 20px;
  color: var(--fg-muted);
  max-width: 560px;
  line-height: 1.6;
}

/* ── MATH SECTION ── */
.math-section {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 24px 120px;
}

.math-headline {
  font-family: var(--font-heading);
  font-size: 15px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--accent);
  margin-bottom: 40px;
}

.math-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2px;
  background: var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.math-card {
  background: var(--bg-elevated);
  padding: 40px 32px;
}

.math-card .number {
  font-family: var(--font-heading);
  font-size: 48px;
  font-weight: 700;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
}

.math-card .label {
  font-size: 15px;
  color: var(--fg-muted);
}

/* ── HOW IT WORKS ── */
.how-section {
  background: var(--bg-elevated);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 100px 24px;
}

.how-inner {
  max-width: 900px;
  margin: 0 auto;
}

.how-section h2 {
  font-family: var(--font-heading);
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 700;
  letter-spacing: -1.5px;
  margin-bottom: 60px;
}

.steps {
  display: flex;
  flex-direction: column;
  gap: 48px;
}

.step {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 24px;
  align-items: start;
}

.step-num {
  font-family: var(--font-heading);
  font-size: 40px;
  font-weight: 700;
  color: var(--accent-dim);
  opacity: 0.5;
  line-height: 1;
}

.step h3 {
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.3px;
}

.step p {
  color: var(--fg-muted);
  font-size: 16px;
}

/* ── COMPARE ── */
.compare-section {
  max-width: 900px;
  margin: 0 auto;
  padding: 100px 24px;
}

.compare-section h2 {
  font-family: var(--font-heading);
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 700;
  letter-spacing: -1.5px;
  margin-bottom: 48px;
}

.compare-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  background: var(--bg-elevated);
  border-radius: var(--radius);
  overflow: hidden;
}

.compare-table th,
.compare-table td {
  padding: 20px 24px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.compare-table thead th {
  font-family: var(--font-heading);
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--fg-muted);
  background: var(--bg-card);
}

.compare-table tbody td {
  font-size: 16px;
  color: var(--fg-muted);
}

.compare-table tbody td:first-child {
  font-weight: 600;
  color: var(--fg);
}

.compare-table tr:last-child td {
  border-bottom: none;
}

.highlight-row td {
  background: var(--accent-glow);
}

.highlight-row td:first-child {
  color: var(--accent) !important;
}

/* ── CLOSING ── */
.closing-section {
  text-align: center;
  padding: 120px 24px;
  position: relative;
}

.closing-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.closing-section h2 {
  font-family: var(--font-heading);
  font-size: clamp(36px, 6vw, 60px);
  font-weight: 700;
  letter-spacing: -2px;
  margin-bottom: 20px;
  position: relative;
  z-index: 1;
}

.closing-section h2 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.closing-section p {
  font-size: 19px;
  color: var(--fg-muted);
  max-width: 500px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

/* ── FOOTER ── */
footer {
  border-top: 1px solid var(--border);
  padding: 40px 24px;
  text-align: center;
}

footer p {
  font-size: 14px;
  color: var(--fg-muted);
}

footer a {
  color: var(--accent);
  text-decoration: none;
}

/* ── HERO CTA ── */
.hero-cta {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-top: 40px;
  flex-wrap: wrap;
}

.hero-browse {
  font-size: 16px;
  color: var(--fg-muted);
  text-decoration: none;
  transition: color 0.2s;
}
.hero-browse:hover { color: var(--fg); }

.closing-cta { margin-top: 40px; position: relative; z-index: 1; }

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .math-grid {
    grid-template-columns: 1fr;
  }
  
  .step {
    grid-template-columns: 48px 1fr;
    gap: 16px;
  }
  
  .step-num {
    font-size: 32px;
  }
  
  .compare-table {
    font-size: 14px;
  }
  
  .compare-table th,
  .compare-table td {
    padding: 14px 16px;
  }
  
  .hero {
    padding: 48px 24px 72px;
  }
  
  .closing-section {
    padding: 80px 24px;
  }
}