/* ============================================================
   NEURO GENETICS INSTITUTE — GLOBAL BRAND STYLESHEET
   Design language: clinical, credible, warm.
   Charcoal canvas · synapse-amber accent · teal secondary.
   Inter (sans) + Courier New (monospace data readouts).
   ============================================================ */

/* ---------- RESET & BASE ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: #07070b;
  color: #e4e4e7;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

::selection { background: rgba(251, 191, 36, 0.3); color: #fafafa; }

/* ---------- DESIGN TOKENS ---------- */
:root {
  --bg: #07070b;
  --bg-1: #0a0a12;
  --panel: #0d0d14;
  --panel-2: #12121a;
  --border: #1f1f26;
  --border-2: #2a2a33;
  --text: #fafafa;
  --text-2: #d4d4d8;
  --text-3: #a1a1aa;
  --text-4: #71717a;
  --text-5: #52525b;
  --amber: #fbbf24;
  --amber-dim: rgba(251, 191, 36, 0.3);
  --amber-glow: rgba(251, 191, 36, 0.08);
  --teal: #2dd4bf;
  --teal-dim: rgba(45, 212, 191, 0.3);
  --teal-glow: rgba(45, 212, 191, 0.08);
  --green: #22c55e;
  --red: #ef4444;
  --mono: 'Courier New', 'Courier', monospace;
}

/* ---------- TYPOGRAPHY ---------- */
h1, h2, h3, h4, h5 {
  font-family: 'Inter', sans-serif;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--text);
}
h1 { font-size: clamp(2.5rem, 6vw, 4.5rem); }
h2 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); margin-bottom: 1rem; }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.5rem); margin-bottom: 0.75rem; color: var(--amber); }
h4 { font-size: 1.1rem; margin-bottom: 0.5rem; color: var(--text); }
p { margin-bottom: 1.25rem; color: var(--text-2); font-size: 1.05rem; }
strong { color: var(--text); font-weight: 600; }
em { color: var(--amber); font-style: italic; }
a { color: var(--amber); text-decoration: none; transition: opacity 0.2s; }
a:hover { opacity: 0.8; text-decoration: underline; }

/* ---------- NAVIGATION BAR ---------- */
.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  background: rgba(7, 7, 11, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.nav-brand { display: flex; align-items: center; gap: 0.75rem; text-decoration: none; }
.nav-brand span { font-size: 0.95rem; font-weight: 700; color: var(--text); letter-spacing: 0.01em; }
.nav-logo { height: 36px; width: auto; }
.nav-links { display: flex; align-items: center; gap: 0.35rem; list-style: none; }
.nav-links a {
  display: block;
  padding: 0.5rem 1rem;
  color: var(--text-2);
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: 8px;
  text-decoration: none;
  transition: all 0.2s ease;
}
.nav-links a:hover { color: var(--text); background: rgba(255,255,255,0.04); text-decoration: none; opacity: 1; }
.nav-links a.active { color: var(--amber); background: var(--amber-glow); }
.nav-cta {
  padding: 0.55rem 1.25rem;
  background: var(--amber);
  color: #07070b !important;
  border-radius: 8px;
  font-weight: 700;
  font-size: 0.9rem;
  margin-left: 0.5rem;
  transition: all 0.2s ease;
}
.nav-cta:hover { background: #fcd34d; text-decoration: none; opacity: 1; }

/* mobile nav toggle */
.nav-toggle { display: none; background: none; border: 1px solid var(--border); border-radius: 8px; padding: 0.5rem 0.7rem; cursor: pointer; color: var(--text); font-size: 1.2rem; }

/* live streak chip in nav */
.nav-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--amber);
  padding: 0.35rem 0.7rem;
  border: 1px solid var(--amber-dim);
  border-radius: 999px;
  background: var(--amber-glow);
  letter-spacing: 0.05em;
  margin-right: 0.5rem;
}
.nav-chip b { color: var(--text); }

/* ---------- PAGE LAYOUT ---------- */
.page {
  position: relative;
  background:
    radial-gradient(ellipse at top, rgba(251, 191, 36, 0.03) 0%, transparent 50%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-1) 100%);
  border-bottom: 1px solid var(--border);
}
.page-inner { max-width: 1100px; margin: 0 auto; width: 100%; }
.section { padding: 5rem 2rem; }
.section-sm { padding: 3rem 2rem; }
.section-header { margin-bottom: 3rem; padding-bottom: 2rem; border-bottom: 1px solid var(--border); }
.section-number {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--amber);
  letter-spacing: 0.2em;
  margin-bottom: 1rem;
  padding: 0.35rem 0.85rem;
  border: 1px solid var(--amber-dim);
  border-radius: 4px;
  background: var(--amber-glow);
}

/* ---------- HERO / COVER ---------- */
.hero {
  min-height: 90vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 6rem 2rem 4rem;
  position: relative;
  background:
    radial-gradient(circle at 50% 40%, rgba(251, 191, 36, 0.12) 0%, transparent 60%),
    radial-gradient(circle at 20% 80%, rgba(45, 212, 191, 0.06) 0%, transparent 50%),
    var(--bg);
  overflow: hidden;
}
/* neuron grid texture */
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(251, 191, 36, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(251, 191, 36, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  mask-image: radial-gradient(ellipse at center, black 0%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 0%, transparent 75%);
}
.hero-kicker {
  font-size: 0.85rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--amber);
  margin-bottom: 1.5rem;
  font-weight: 600;
  position: relative;
}
.hero h1 {
  background: linear-gradient(135deg, var(--text) 0%, var(--amber) 50%, var(--text) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 1.25rem;
  max-width: 900px;
  position: relative;
}
.hero-subtitle {
  font-size: clamp(1.1rem, 2.5vw, 1.4rem);
  color: var(--text-3);
  max-width: 720px;
  margin: 0 auto 2.5rem;
  position: relative;
}
.hero-logo-big {
  width: 130px; height: auto; margin-bottom: 2rem;
  filter: drop-shadow(0 0 40px rgba(251, 191, 36, 0.3));
  position: relative;
}
.hero-features {
  display: flex; gap: 2rem; flex-wrap: wrap; justify-content: center; margin-bottom: 2rem;
  position: relative;
}
.hero-feature { display: flex; align-items: center; gap: 0.5rem; font-size: 0.95rem; color: var(--text-2); }
.hero-feature::before { content: '◆'; color: var(--amber); font-size: 0.65rem; }

.hero-cta-row { display: flex; gap: 1rem; flex-wrap: wrap; justify-content: center; position: relative; }

/* ---------- BUTTONS ---------- */
.btn {
  display: inline-block;
  padding: 0.9rem 2rem;
  font-weight: 700;
  font-size: 1rem;
  border-radius: 8px;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.25s ease;
  font-family: inherit;
}
.btn:hover { text-decoration: none; opacity: 1; }
.btn-primary { background: var(--amber); color: #07070b !important; }
.btn-primary:hover { background: #fcd34d; transform: translateY(-2px); box-shadow: 0 8px 24px rgba(251, 191, 36, 0.25); }
.btn-ghost { background: transparent; color: var(--amber); border-color: var(--amber-dim); }
.btn-ghost:hover { background: var(--amber-glow); border-color: var(--amber); color: var(--text); }
.btn-soft {
  background: transparent; color: var(--amber); border: 1px solid rgba(251, 191, 36, 0.4);
  font-weight: 600; border-radius: 8px; transition: all 0.3s ease;
}
.btn-soft:hover { background: var(--amber-glow); border-color: var(--amber); color: var(--text); }

/* ---------- CARDS ---------- */
.card {
  background: linear-gradient(180deg, var(--panel-2) 0%, var(--panel) 100%);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2.5rem;
  margin-bottom: 1.5rem;
  transition: border-color 0.3s ease;
}
.card:hover { border-color: var(--amber-dim); }
.card-accent { border-left: 4px solid var(--amber); }
.card-teal { border-left: 4px solid var(--teal); }
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}
.mini-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 2rem;
  transition: all 0.25s ease;
}
.mini-card:hover { border-color: var(--amber-dim); transform: translateY(-3px); }
.mini-card-icon { font-size: 2rem; margin-bottom: 1rem; display: block; }

/* clickable lesson/topic cards */
.topic-card {
  display: block;
  background: linear-gradient(180deg, var(--panel-2) 0%, var(--panel) 100%);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.75rem;
  text-decoration: none;
  transition: all 0.25s ease;
  position: relative;
  overflow: hidden;
}
.topic-card:hover { border-color: var(--amber); transform: translateY(-4px); text-decoration: none; }
.topic-card-tag {
  display: inline-block; font-family: var(--mono); font-size: 0.7rem;
  letter-spacing: 0.1em; color: var(--amber); padding: 0.25rem 0.6rem;
  border: 1px solid var(--amber-dim); border-radius: 4px; background: var(--amber-glow);
  margin-bottom: 0.75rem; text-transform: uppercase;
}
.topic-card h4 { font-size: 1.15rem; margin-bottom: 0.4rem; color: var(--text); }
.topic-card p { font-size: 0.92rem; color: var(--text-3); margin: 0; }
.topic-card-arrow { position: absolute; top: 1.75rem; right: 1.75rem; color: var(--text-4); font-size: 1.2rem; transition: all 0.25s ease; }
.topic-card:hover .topic-card-arrow { color: var(--amber); transform: translate(3px, -3px); }

/* ---------- TABLE OF CONTENTS ---------- */
.toc-list { list-style: none; margin: 2rem 0; }
.toc-list li { margin-bottom: 0.75rem; }
.toc-list a {
  display: flex; justify-content: space-between; align-items: center;
  padding: 1.25rem 1.5rem;
  background: var(--panel); border: 1px solid var(--border); border-radius: 8px;
  color: var(--text); font-weight: 500; transition: all 0.2s ease;
}
.toc-list a:hover { border-color: var(--amber); background: var(--amber-glow); text-decoration: none; transform: translateX(4px); }
.toc-list .toc-num { color: var(--amber); font-family: var(--mono); font-weight: 700; margin-right: 1rem; }

/* ---------- COMPARISON TABLE ---------- */
.comparison-table {
  width: 100%; border-collapse: collapse; margin: 2rem 0;
  background: var(--panel); border-radius: 12px; overflow: hidden;
}
.comparison-table th {
  background: var(--panel-2); padding: 1.25rem; text-align: left;
  color: var(--amber); font-weight: 600; font-size: 0.9rem;
  text-transform: uppercase; letter-spacing: 0.1em; border-bottom: 2px solid var(--border);
}
.comparison-table td { padding: 1.25rem; border-bottom: 1px solid var(--border); color: var(--text-2); font-size: 0.95rem; }
.comparison-table tr:last-child td { border-bottom: none; }
.comparison-table .highlight-col { background: var(--amber-glow); border-left: 2px solid var(--amber); border-right: 2px solid var(--amber); }
.check-icon { color: var(--green); font-weight: bold; }
.cross-icon { color: var(--red); }

/* ---------- CALLOUT ---------- */
.callout {
  background: linear-gradient(135deg, rgba(251, 191, 36, 0.08) 0%, rgba(251, 191, 36, 0.02) 100%);
  border: 1px solid rgba(251, 191, 36, 0.25);
  border-radius: 12px; padding: 2rem; margin: 2.5rem 0; position: relative;
}
.callout::before {
  content: '💡'; position: absolute; top: -16px; left: 20px;
  background: var(--bg); padding: 0 0.5rem; font-size: 1.4rem;
}
.callout p { color: var(--text); margin: 0; font-size: 1.1rem; }
.callout-teal {
  background: linear-gradient(135deg, rgba(45, 212, 191, 0.08) 0%, rgba(45, 212, 191, 0.02) 100%);
  border-color: rgba(45, 212, 191, 0.25);
}
.callout-teal::before { content: '🧬'; }

/* ---------- CHECKLIST ---------- */
.checklist { list-style: none; margin: 1.5rem 0; }
.checklist li {
  padding: 1rem 1.25rem; background: var(--panel); border: 1px solid var(--border);
  border-radius: 8px; margin-bottom: 0.75rem;
  display: flex; align-items: flex-start; gap: 1rem;
  color: var(--text-2); font-size: 1.05rem;
}
.checklist li::before { content: '✓'; font-size: 1.4rem; color: var(--green); flex-shrink: 0; font-weight: bold; }

/* ---------- RESULT / STAT BOX ---------- */
.result-box {
  background: linear-gradient(135deg, rgba(251, 191, 36, 0.1) 0%, rgba(45, 212, 191, 0.05) 100%);
  border: 2px solid rgba(251, 191, 36, 0.4);
  border-radius: 14px; padding: 2.5rem; margin: 2.5rem 0; text-align: center;
}
.result-box-label { font-size: 0.85rem; color: var(--amber); letter-spacing: 0.2em; text-transform: uppercase; margin-bottom: 0.75rem; font-weight: 600; }
.result-box-value { font-size: 1.5rem; color: var(--text); font-weight: 700; margin-bottom: 0.75rem; }
.result-box-desc { color: var(--text-2); font-size: 1.05rem; }

/* ---------- LESSON BLOCK (Science curriculum template) ---------- */
.lesson-block {
  background: linear-gradient(180deg, var(--panel-2) 0%, var(--panel) 100%);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 0;
  margin-bottom: 2.5rem;
  overflow: hidden;
}
.lesson-block-header {
  padding: 1.75rem 2rem;
  border-bottom: 1px solid var(--border);
  background: rgba(251, 191, 36, 0.02);
}
.lesson-block-num {
  font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.15em;
  color: var(--amber); text-transform: uppercase; margin-bottom: 0.4rem;
}
.lesson-block-header h3 { margin-bottom: 0.35rem; }
.lesson-block-header p { margin: 0; font-size: 0.95rem; color: var(--text-3); }
.lesson-meta { display: flex; gap: 0.5rem; flex-wrap: wrap; margin-top: 0.85rem; }
.lesson-meta span {
  font-family: var(--mono); font-size: 0.7rem; padding: 0.25rem 0.6rem;
  border: 1px solid var(--border-2); border-radius: 4px; color: var(--text-3);
  background: var(--bg);
}
.lesson-meta span.exam { color: var(--amber); border-color: var(--amber-dim); background: var(--amber-glow); }

.lesson-video {
  padding: 2rem;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.lesson-video-label {
  font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.15em;
  color: var(--teal); text-transform: uppercase; margin-bottom: 1rem;
  display: flex; align-items: center; gap: 0.5rem;
}
.video-frame {
  position: relative; width: 100%; aspect-ratio: 16 / 9;
  background: var(--panel-2); border: 1px dashed var(--border-2);
  border-radius: 10px; display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 0.75rem; color: var(--text-4);
  text-align: center; padding: 2rem;
}
.video-frame.empty::before { content: '▶'; font-size: 2.5rem; color: var(--text-5); }
.video-frame small { font-size: 0.8rem; color: var(--text-5); }
.video-frame.has-video { padding: 0; border-style: solid; border-color: var(--border); }
.video-frame iframe, .video-frame embed { width: 100%; height: 100%; border: 0; border-radius: 10px; display: block; }

.lesson-files {
  padding: 2rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}
.file-slot {
  display: flex; flex-direction: column; gap: 0.5rem;
  padding: 1.25rem;
  background: var(--bg); border: 1px dashed var(--border-2); border-radius: 8px;
  text-decoration: none; transition: all 0.2s ease; min-height: 110px;
}
.file-slot:hover { border-color: var(--teal); text-decoration: none; }
.file-slot-icon { font-size: 1.4rem; }
.file-slot-label { font-size: 0.9rem; font-weight: 600; color: var(--text); }
.file-slot-type { font-family: var(--mono); font-size: 0.7rem; color: var(--teal); letter-spacing: 0.1em; text-transform: uppercase; }
.file-slot.empty .file-slot-label { color: var(--text-4); }
.file-slot.filled { border-style: solid; border-color: var(--teal-dim); background: var(--teal-glow); }

/* ---------- GLOBAL FOOTER ---------- */
.global-footer {
  padding: 5rem 2rem; text-align: center;
  background: #050508; border-top: 1px solid var(--border);
}
.global-footer-logo { width: 70px; height: auto; margin-bottom: 1.5rem; opacity: 0.8; }
.global-footer-brand { font-size: 1.2rem; color: var(--text); font-weight: 600; margin-bottom: 0.5rem; }
.global-footer-tagline { font-size: 1rem; color: var(--text-4); font-style: italic; margin-bottom: 2.5rem; }
.cta-box {
  background: linear-gradient(135deg, rgba(251, 191, 36, 0.05) 0%, rgba(251, 191, 36, 0.01) 100%);
  border: 1px solid rgba(251, 191, 36, 0.15);
  border-radius: 16px; padding: 3rem 2rem; max-width: 750px; margin: 0 auto 2.5rem;
}
.cta-box h3 { color: var(--text); margin-bottom: 1rem; font-size: 1.6rem; font-weight: 600; }
.cta-box p { color: var(--text-2); margin-bottom: 0.75rem; font-size: 1.05rem; line-height: 1.6; }
.cta-box a { color: var(--amber); font-weight: 600; }
.footer-legal { font-size: 0.8rem; color: var(--text-5); max-width: 650px; margin: 0 auto; line-height: 1.6; }

/* ---------- UTILITIES ---------- */
.text-center { text-align: center; }
.text-teal { color: var(--teal); }
.text-amber { color: var(--amber); }
.mono { font-family: var(--mono); }
.muted { color: var(--text-3); }
.muted-2 { color: var(--text-4); }
.stack > * + * { margin-top: 1rem; }
.divider { height: 1px; background: var(--border); margin: 3rem 0; border: 0; }
.tag-row { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.pill {
  display: inline-block; font-family: var(--mono); font-size: 0.7rem;
  letter-spacing: 0.1em; color: var(--teal); padding: 0.25rem 0.6rem;
  border: 1px solid var(--teal-dim); border-radius: 4px; background: var(--teal-glow);
  text-transform: uppercase;
}

/* ---------- RESPONSIVE ---------- */
@media (max-width: 860px) {
  .nav-toggle { display: inline-block; }
  .nav-links {
    position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: rgba(7,7,11,0.98); backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    padding: 0.5rem; display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 0.85rem 1rem; }
  .nav-cta { margin: 0.5rem 1rem 0; text-align: center; }
}
@media (max-width: 640px) {
  .section { padding: 3.5rem 1.25rem; }
  .navbar { padding: 0.75rem 1.25rem; }
  .card { padding: 1.5rem; }
  .lesson-block-header, .lesson-video, .lesson-files { padding-left: 1.25rem; padding-right: 1.25rem; }
  .comparison-table { font-size: 0.85rem; }
  .comparison-table th, .comparison-table td { padding: 0.75rem; }
  .hero { padding: 5rem 1.25rem 3rem; min-height: auto; }
}