:root {
  --bg: #0a0a0f;
  --bg-surface: #12121a;
  --bg-elevated: #1a1a26;
  --fg: #e8e8ed;
  --fg-muted: #8888a0;
  --fg-subtle: #55556a;
  --accent: #4ade80;
  --accent-dim: #22c55e;
  --accent-glow: rgba(74, 222, 128, 0.12);
  --border: #2a2a3a;
  --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 {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* ---- HERO ---- */
.hero {
  min-height: 90vh;
  display: flex;
  align-items: center;
  padding: 6rem 2rem 4rem;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -40%;
  right: -20%;
  width: 70vw;
  height: 70vw;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 65%);
  pointer-events: none;
}

.hero-grid {
  max-width: 1100px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-block;
  padding: 0.4rem 1rem;
  border: 1px solid var(--border);
  border-radius: 100px;
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--fg-muted);
  margin-bottom: 2rem;
  letter-spacing: 0.02em;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 6vw, 4.5rem);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
}

.hero h1 .accent {
  color: var(--accent);
}

.lede {
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  color: var(--fg-muted);
  max-width: 600px;
  line-height: 1.65;
  margin-bottom: 3.5rem;
}

.hero-stats {
  display: flex;
  gap: 3rem;
  flex-wrap: wrap;
}

.stat {
  display: flex;
  flex-direction: column;
}

.stat-number {
  font-family: var(--font-display);
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 0.3rem;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--fg-muted);
  max-width: 180px;
}

/* ---- PROBLEM ---- */
.problem {
  padding: 6rem 2rem;
  border-top: 1px solid var(--border);
}

.problem-inner {
  max-width: 1100px;
  margin: 0 auto;
}

.section-label {
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--accent);
  margin-bottom: 1rem;
}

.problem h2, .services h2, .math h2 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: 3rem;
}

.problem-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.problem-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
}

.problem-icon {
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--accent-dim);
  margin-bottom: 1rem;
}

.problem-card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.6rem;
  letter-spacing: -0.01em;
}

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

/* ---- SERVICES ---- */
.services {
  padding: 6rem 2rem;
  border-top: 1px solid var(--border);
}

.services-inner {
  max-width: 1100px;
  margin: 0 auto;
}

.service-blocks {
  display: grid;
  gap: 1.5rem;
}

.service-block {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2.5rem;
  transition: border-color 0.3s;
}

.service-block:hover {
  border-color: var(--accent-dim);
}

.service-main {
  background: linear-gradient(135deg, var(--bg-elevated) 0%, var(--bg-surface) 100%);
  border-color: var(--accent-dim);
  grid-column: 1 / -1;
}

.service-tag {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
  background: var(--accent-glow);
  padding: 0.3rem 0.8rem;
  border-radius: 100px;
  margin-bottom: 1.2rem;
}

.service-block h3 {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.8rem;
}

.service-block p {
  color: var(--fg-muted);
  font-size: 1rem;
  line-height: 1.65;
  margin-bottom: 1.5rem;
  max-width: 680px;
}

.service-detail {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--fg);
}

.dot {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--fg-subtle);
  display: inline-block;
}

/* ---- MATH ---- */
.math {
  padding: 6rem 2rem;
  border-top: 1px solid var(--border);
  background: var(--bg-surface);
}

.math-inner {
  max-width: 900px;
  margin: 0 auto;
  text-align: center;
}

.math-equation {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  margin: 3rem 0;
  flex-wrap: wrap;
}

.math-box {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem 2.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 220px;
}

.math-box.highlight {
  border-color: var(--accent);
  background: linear-gradient(180deg, rgba(74, 222, 128, 0.06) 0%, var(--bg) 100%);
}

.math-label {
  font-size: 0.85rem;
  color: var(--fg-muted);
  margin-bottom: 0.5rem;
}

.math-value {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
}

.math-box.highlight .math-value {
  color: var(--accent);
}

.math-operator {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--fg-subtle);
}

.math-conclusion {
  font-size: 1.05rem;
  color: var(--fg-muted);
  line-height: 1.65;
  max-width: 600px;
  margin: 0 auto;
}

/* ---- CLOSING ---- */
.closing {
  padding: 8rem 2rem;
  border-top: 1px solid var(--border);
  text-align: center;
}

.closing-inner {
  max-width: 800px;
  margin: 0 auto;
}

.closing h2 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 1.5rem;
}

.closing-text {
  font-size: 1.1rem;
  color: var(--fg-muted);
  line-height: 1.7;
  max-width: 620px;
  margin: 0 auto;
}

/* ---- FOOTER ---- */
.site-footer {
  padding: 3rem 2rem;
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
}

.footer-brand {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

.footer-details {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.8rem;
  font-size: 0.85rem;
  color: var(--fg-muted);
  margin-bottom: 0.5rem;
}

.footer-tagline {
  font-size: 0.8rem;
  color: var(--fg-subtle);
  font-style: italic;
}

/* ---- RESPONSIVE ---- */
@media (max-width: 768px) {
  .hero {
    min-height: auto;
    padding: 4rem 1.5rem 3rem;
  }

  .hero-stats {
    gap: 2rem;
  }

  .stat-number {
    font-size: 1.8rem;
  }

  .problem, .services, .math {
    padding: 4rem 1.5rem;
  }

  .closing {
    padding: 5rem 1.5rem;
  }

  .service-blocks {
    grid-template-columns: 1fr;
  }

  .service-main {
    grid-column: 1;
  }

  .math-equation {
    flex-direction: column;
    gap: 1rem;
  }

  .math-box {
    width: 100%;
    min-width: unset;
  }

  .footer-details {
    flex-direction: column;
    gap: 0.3rem;
  }

  .footer-details .dot {
    display: none;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 2rem;
  }

  .hero-stats {
    flex-direction: column;
    gap: 1.5rem;
  }

  .stat-label {
    max-width: 100%;
  }

  .service-detail {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.3rem;
  }

  .service-detail .dot {
    display: none;
  }
}