:root {
  --bg: #0b0d12;
  --bg-elevated: #12151c;
  --bg-card: #161a22;
  --border: #262b36;
  --text: #eef0f4;
  --text-dim: #a3aab8;
  --text-faint: #6b7280;
  --accent: #6ee7c9;
  --accent-strong: #3ecfa8;
  --accent-soft: rgba(110, 231, 201, 0.12);
  --font-display: 'Fraunces', serif;
  --font-body: 'Inter', sans-serif;
  --radius: 14px;
  --max-width: 1120px;
}

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

html { scroll-behavior: smooth; }

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

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.15;
  letter-spacing: -0.01em;
}

a { color: inherit; text-decoration: none; }

section, header, footer {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 32px;
}

/* HEADER */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 32px;
  max-width: var(--max-width);
  gap: 24px;
}

.brand {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 600;
  color: var(--text);
}
.brand-dot { color: var(--accent); }

.main-nav {
  display: flex;
  gap: 28px;
  font-size: 15px;
  color: var(--text-dim);
}
.main-nav a:hover { color: var(--text); }
.main-nav a.active { color: var(--accent); }

.nav-cta {
  background: var(--accent);
  color: #06110d;
  font-weight: 600;
  font-size: 14px;
  padding: 10px 20px;
  border-radius: 999px;
  white-space: nowrap;
}
.nav-cta:hover { background: var(--accent-strong); }

.sub-nav {
  display: flex;
  gap: 8px;
  padding: 14px 32px 0;
  max-width: var(--max-width);
  margin: 0 auto;
  border-bottom: 1px solid var(--border);
}
.sub-nav a {
  font-size: 14px;
  color: var(--text-dim);
  padding: 10px 16px;
  border-radius: 8px 8px 0 0;
  border-bottom: 2px solid transparent;
}
.sub-nav a.active {
  color: var(--text);
  border-bottom: 2px solid var(--accent);
}
.sub-nav a:hover { color: var(--text); }

/* HERO */
.hero {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
  padding-top: 64px;
  padding-bottom: 80px;
}
.hero-kicker {
  color: var(--accent);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 18px;
}
.hero h1 {
  font-size: 46px;
  margin-bottom: 22px;
}
.hero-sub {
  font-size: 18px;
  color: var(--text-dim);
  max-width: 46ch;
  margin-bottom: 32px;
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 26px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 15px;
  transition: all 0.15s ease;
}
.btn-primary {
  background: var(--accent);
  color: #06110d;
}
.btn-primary:hover { background: var(--accent-strong); transform: translateY(-1px); }
.btn-ghost {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
}
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn-large { padding: 16px 34px; font-size: 16px; }

.hero-visual { display: flex; align-items: center; justify-content: center; }
.network-graphic { width: 100%; max-width: 380px; }
.net-nodes circle { filter: drop-shadow(0 0 6px var(--accent)); }

/* WHY */
.why { padding: 60px 32px; }
.why h2 { font-size: 30px; margin-bottom: 36px; }
.why-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.why-item h3 { font-size: 19px; margin: 14px 0 10px; color: var(--text); }
.why-item p { color: var(--text-dim); font-size: 15px; }
.why-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
  font-size: 14px;
}

/* CURRICULUM */
.curriculum { padding: 60px 32px; }
.curriculum h2 { font-size: 30px; }
.curriculum-sub { color: var(--text-dim); margin: 10px 0 36px; font-size: 16px; }

.module-list { display: flex; flex-direction: column; gap: 16px; }
.module {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 24px;
  padding: 26px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color 0.15s ease;
}
.module:hover { border-color: var(--accent); }
.module-mark {
  color: var(--accent);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.02em;
}
.module-body h3 { font-size: 19px; margin-bottom: 8px; }
.module-body p { color: var(--text-dim); font-size: 15px; }

/* WHO */
.who { padding: 60px 32px; }
.who h2 { font-size: 30px; margin-bottom: 20px; }
.who p { color: var(--text-dim); font-size: 17px; max-width: 68ch; }
.who strong { color: var(--text); }

/* BOOK */
.book {
  padding: 80px 32px;
  text-align: center;
  background: var(--bg-elevated);
  border-radius: 24px;
  margin: 60px auto;
}
.book h2 { font-size: 32px; margin-bottom: 14px; }
.book p { color: var(--text-dim); font-size: 17px; margin-bottom: 28px; }
.book-note { font-size: 13px; color: var(--text-faint); margin-top: 14px; }

/* CARD GRIDS (courses/projects) */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 22px;
  padding: 40px 0 60px;
}
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px;
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 4px 10px;
  border-radius: 999px;
  margin-bottom: 14px;
}
.card h3 { font-size: 18px; margin-bottom: 8px; }
.card p { color: var(--text-dim); font-size: 14px; }

.page-hero {
  padding: 56px 32px 20px;
}
.page-hero h1 { font-size: 36px; margin-bottom: 12px; }
.page-hero p { color: var(--text-dim); font-size: 17px; max-width: 60ch; }

/* FOOTER */
.site-footer {
  padding: 40px 32px 60px;
  text-align: center;
  border-top: 1px solid var(--border);
  margin-top: 40px;
}
.footer-nav {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 16px;
  font-size: 14px;
  color: var(--text-dim);
}
.footer-nav a:hover { color: var(--accent); }
.site-footer p { color: var(--text-faint); font-size: 13px; }

@media (max-width: 860px) {
  .hero { grid-template-columns: 1fr; padding-top: 40px; }
  .hero h1 { font-size: 34px; }
  .hero-visual { display: none; }
  .why-grid { grid-template-columns: 1fr; }
  .module { grid-template-columns: 1fr; gap: 10px; }
  .main-nav { display: none; }
  .site-header { justify-content: space-between; }
}