/* GTH Nature Notes — unofficial educational guide (distinct from .ca example) */
:root {
  --ink: #0f172a;
  --ink-soft: #334155;
  --muted: #64748b;
  --paper: #f8fafc;
  --card: #ffffff;
  --line: #e2e8f0;
  --brand: #0ea5e9;
  --brand-dark: #0369a1;
  --accent: #f59e0b;
  --accent-soft: #fef3c7;
  --radius: 14px;
  --shadow: 0 10px 40px rgba(15, 23, 42, 0.08);
  --font-sans: "Outfit", system-ui, sans-serif;
  --font-serif: "Source Serif 4", Georgia, serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.65;
  color: var(--ink-soft);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--brand-dark); text-decoration: none; transition: color .2s; }
a:hover { color: var(--brand); }
img { max-width: 100%; height: auto; display: block; }

.container { max-width: 1080px; margin: 0 auto; padding: 0 1.25rem; }

/* Top bar */
.disclaimer-bar {
  background: linear-gradient(90deg, #0c4a6e, #075985);
  color: #e0f2fe;
  text-align: center;
  font-size: 0.8rem;
  padding: 0.45rem 1rem;
  letter-spacing: 0.02em;
}

/* Nav */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(248, 250, 252, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 0;
  gap: 1rem;
}
.brand {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.brand span { color: var(--brand); }
.nav-links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.25rem;
  align-items: center;
}
.nav-links a {
  color: var(--ink-soft);
  font-weight: 500;
  font-size: 0.92rem;
  padding: 0.35rem 0;
  border-bottom: 2px solid transparent;
}
.nav-links a:hover, .nav-links a.active {
  color: var(--brand-dark);
  border-bottom-color: var(--accent);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}
.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
}
@media (max-width: 900px) {
  .nav-toggle { display: flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--card);
    flex-direction: column;
    padding: 1rem 1.25rem 1.25rem;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
  }
  .nav-links.open { display: flex; }
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.35rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform .15s, box-shadow .2s;
}
.btn-primary {
  background: linear-gradient(135deg, var(--brand), var(--brand-dark));
  color: #fff;
  box-shadow: 0 4px 14px rgba(14, 165, 233, 0.35);
}
.btn-primary:hover { transform: translateY(-1px); color: #fff; }
.btn-ghost {
  background: transparent;
  border-color: rgba(255,255,255,0.55);
  color: #fff;
}
.btn-ghost:hover { background: rgba(255,255,255,0.12); color: #fff; }
.btn-outline {
  background: var(--card);
  border-color: var(--line);
  color: var(--ink);
}
.btn-outline:hover { border-color: var(--brand); color: var(--brand-dark); }

/* Hero */
.hero {
  position: relative;
  padding: 4rem 0 4.5rem;
  overflow: hidden;
  background: linear-gradient(145deg, #0c4a6e 0%, #164e63 45%, #0f172a 100%);
  color: #e2e8f0;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 80% 20%, rgba(245, 158, 11, 0.15), transparent),
    radial-gradient(ellipse 50% 50% at 10% 80%, rgba(14, 165, 233, 0.2), transparent);
  pointer-events: none;
}
.hero .container { position: relative; z-index: 1; }
.hero-badge {
  display: inline-block;
  background: var(--accent-soft);
  color: #92400e;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  margin-bottom: 1.25rem;
}
.hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  color: #fff;
  line-height: 1.15;
  margin-bottom: 1rem;
  max-width: 18ch;
}
.hero-lead {
  font-size: 1.1rem;
  max-width: 42rem;
  opacity: 0.92;
  margin-bottom: 1.75rem;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-bottom: 2.5rem; }
.stat-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  max-width: 520px;
}
.stat {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--radius);
  padding: 1rem;
  text-align: center;
}
.stat strong {
  display: block;
  font-size: 1.5rem;
  color: #fff;
  font-family: var(--font-serif);
}
.stat span { font-size: 0.8rem; opacity: 0.85; }
@media (max-width: 600px) {
  .stat-row { grid-template-columns: 1fr; }
}

/* Sections */
section { padding: 3.5rem 0; }
.section-title {
  font-family: var(--font-serif);
  font-size: 1.85rem;
  color: var(--ink);
  margin-bottom: 0.5rem;
}
.section-kicker {
  color: var(--brand-dark);
  font-weight: 700;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.35rem;
}
.section-intro { max-width: 40rem; margin-bottom: 2rem; color: var(--muted); }

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
}
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}
.card h3 { color: var(--ink); margin-bottom: 0.5rem; font-size: 1.1rem; }
.card p { color: var(--muted); font-size: 0.95rem; }
.card-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--accent-soft);
  color: #b45309;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

/* Article list */
.article-grid {
  display: grid;
  gap: 1.5rem;
}
.article-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 280px);
  gap: 1.5rem;
  background: var(--card);
  border-radius: var(--radius);
  border: 1px solid var(--line);
  overflow: hidden;
  box-shadow: var(--shadow);
}
@media (max-width: 800px) {
  .article-card { grid-template-columns: 1fr; }
}
.article-visual {
  min-height: 200px;
  background: linear-gradient(135deg, #bae6fd, #fde68a);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
}
.article-body { padding: 1.75rem; }
.article-body h2, .article-body h3 { font-family: var(--font-serif); color: var(--ink); margin-bottom: 0.75rem; }
.article-meta { font-size: 0.85rem; color: var(--muted); margin-top: 1rem; }
.tag {
  display: inline-block;
  background: #e0f2fe;
  color: var(--brand-dark);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.25rem 0.6rem;
  border-radius: 6px;
  margin-bottom: 0.5rem;
}

/* Page content */
.page-hero {
  padding: 2.5rem 0 1rem;
  background: linear-gradient(180deg, #e0f2fe, var(--paper));
}
.page-hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 4vw, 2.35rem);
  color: var(--ink);
  margin-bottom: 0.5rem;
}
.prose {
  max-width: 720px;
  margin: 0 auto;
  padding: 2rem 0 4rem;
}
.prose h2 { font-family: var(--font-serif); color: var(--ink); margin: 2rem 0 0.75rem; font-size: 1.35rem; }
.prose p { margin-bottom: 1rem; }
.prose ul { margin: 0 0 1rem 1.25rem; }
.prose li { margin-bottom: 0.35rem; }

/* Forms */
.form-group { margin-bottom: 1rem; }
.form-group label { display: block; font-weight: 600; margin-bottom: 0.35rem; color: var(--ink); }
.form-group input, .form-group textarea {
  width: 100%;
  padding: 0.65rem 0.85rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  font-family: inherit;
  font-size: 1rem;
}
.form-group textarea { min-height: 140px; resize: vertical; }

/* Cookie */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--ink);
  color: #e2e8f0;
  padding: 1rem;
  z-index: 9999;
  box-shadow: 0 -8px 30px rgba(0,0,0,0.15);
}
.cookie-inner {
  max-width: 1080px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  justify-content: space-between;
}
.cookie-inner p { flex: 1; min-width: 200px; font-size: 0.9rem; }

/* Footer */
.site-footer {
  background: var(--ink);
  color: #94a3b8;
  padding: 2.5rem 0;
  font-size: 0.9rem;
}
.site-footer a { color: #cbd5e1; }
.site-footer a:hover { color: #fff; }
.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}
.site-footer h4 { color: #fff; font-size: 0.85rem; margin-bottom: 0.75rem; text-transform: uppercase; letter-spacing: 0.05em; }
.footer-bottom {
  border-top: 1px solid #334155;
  padding-top: 1.25rem;
  font-size: 0.8rem;
}