/* FlightDecide — shared styles for /tools/ and /learn/ pages */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --bg: #0F172A;
  --bg-card: rgba(255,255,255,0.04);
  --bg-card-hover: rgba(255,255,255,0.07);
  --border: rgba(255,255,255,0.08);
  --border-bright: rgba(255,255,255,0.15);
  --accent-green: #22C55E;
  --accent-blue: #3B82F6;
  --accent-amber: #EAB308;
  --accent-red: #EF4444;
  --text: #F0F0F5;
  --text-muted: #94A3B8;
  --text-dim: #64748B;
  --radius: 16px;
  --radius-sm: 10px;
  --max-content: 800px;
}
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  font-size: 17px;
}

/* NAV */
nav.site-nav {
  position: sticky;
  top: 0;
  background: rgba(15,23,42,0.9);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  height: 60px;
  z-index: 100;
}
.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 40px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  font-size: 15px;
}
.nav-logo-icon {
  width: 24px;
  height: 24px;
  border-radius: 6px;
  background: linear-gradient(135deg, var(--accent-green), var(--accent-blue));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
}
.nav-back {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: color 0.2s;
}
.nav-back:hover { color: var(--text); }

/* HERO */
.page-hero {
  padding: 64px 40px 56px;
  text-align: center;
  background:
    radial-gradient(ellipse 60% 80% at 50% 0%, rgba(34,197,94,0.07) 0%, transparent 60%),
    var(--bg);
  border-bottom: 1px solid var(--border);
}
.page-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  background: linear-gradient(135deg, var(--accent-green), var(--accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: block;
  margin-bottom: 12px;
}
.page-hero h1 {
  font-size: 40px;
  font-weight: 800;
  letter-spacing: -1.5px;
  line-height: 1.1;
  margin-bottom: 14px;
}
.page-sub {
  font-size: 17px;
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.6;
}
.page-wrap {
  max-width: var(--max-content);
  margin: 0 auto;
  padding: 56px 40px 100px;
}
.section-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--text-muted);
  display: block;
  margin-bottom: 20px;
}
.crumbs {
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 28px;
}
.crumbs a { color: var(--text-muted); text-decoration: none; }
.crumbs a:hover { color: var(--text); }

/* PROSE (articles) */
.prose h2 {
  font-size: 26px;
  font-weight: 750;
  letter-spacing: -0.5px;
  line-height: 1.25;
  margin: 44px 0 14px;
}
.prose h3 {
  font-size: 19px;
  font-weight: 700;
  margin: 30px 0 10px;
}
.prose p { margin-bottom: 16px; color: var(--text); }
.prose p.lede {
  font-size: 19px;
  line-height: 1.65;
  color: var(--text);
  padding: 20px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent-green);
  border-radius: var(--radius-sm);
  margin-bottom: 28px;
}
.prose ul, .prose ol { margin: 0 0 16px 24px; }
.prose li { margin-bottom: 8px; }
.prose a { color: var(--accent-blue); text-decoration: none; }
.prose a:hover { text-decoration: underline; }
.prose strong { font-weight: 650; }
.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0 24px;
  font-size: 15px;
}
.prose th, .prose td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
.prose th { color: var(--text-muted); font-weight: 650; font-size: 13px; text-transform: uppercase; letter-spacing: 1px; }
.prose .table-scroll { overflow-x: auto; }
.prose code {
  font-family: ui-monospace, 'SF Mono', Menlo, monospace;
  font-size: 15px;
  background: rgba(255,255,255,0.07);
  border-radius: 5px;
  padding: 1px 6px;
}
.prose pre {
  font-family: ui-monospace, 'SF Mono', Menlo, monospace;
  font-size: 14px;
  background: rgba(0,0,0,0.35);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  overflow-x: auto;
  margin: 0 0 20px;
  line-height: 1.6;
}
.byline {
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 32px;
}
.callout {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent-amber);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  margin: 20px 0 24px;
  font-size: 15px;
  color: var(--text-muted);
}
.callout strong { color: var(--text); }

/* CALCULATOR */
.calc-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 32px;
}
.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px 22px;
  margin-bottom: 8px;
}
.calc-field label {
  display: block;
  font-size: 13px;
  font-weight: 650;
  color: var(--text-muted);
  margin-bottom: 6px;
}
.calc-field input, .calc-field select {
  width: 100%;
  background: rgba(0,0,0,0.3);
  border: 1px solid var(--border-bright);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 17px;
  padding: 10px 12px;
  font-family: inherit;
}
.calc-field input:focus, .calc-field select:focus {
  outline: none;
  border-color: var(--accent-blue);
}
.calc-hint { font-size: 12px; color: var(--text-dim); margin-top: 5px; }
.calc-results {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 14px;
  margin-top: 22px;
}
.result-tile {
  background: rgba(0,0,0,0.25);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px;
  text-align: center;
}
.result-tile .result-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--text-muted);
  display: block;
  margin-bottom: 6px;
}
.result-tile .result-value {
  font-size: 30px;
  font-weight: 800;
  letter-spacing: -1px;
  line-height: 1.1;
}
.result-tile .result-note { font-size: 12px; color: var(--text-dim); margin-top: 4px; }
.result-green .result-value { color: var(--accent-green); }
.result-amber .result-value { color: var(--accent-amber); }
.result-red .result-value { color: var(--accent-red); }
.result-blue .result-value { color: var(--accent-blue); }

/* FAQ (matches support.html behavior) */
.faq-list { display: flex; flex-direction: column; gap: 12px; margin-bottom: 8px; }
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color 0.2s;
}
.faq-item:hover { border-color: rgba(34,197,94,0.2); }
.faq-item.open { border-color: rgba(34,197,94,0.25); }
.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  background: none;
  border: none;
  color: var(--text);
  font-family: inherit;
  font-size: 16px;
  font-weight: 650;
  text-align: left;
  padding: 16px 20px;
  cursor: pointer;
}
.faq-question:hover { background: var(--bg-card-hover); }
.faq-chevron { flex: none; transition: transform 0.25s; color: var(--text-muted); }
.faq-item.open .faq-chevron { transform: rotate(180deg); }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.3s ease; }
.faq-item.open .faq-answer { max-height: 800px; }
.faq-answer-inner { padding: 0 20px 18px; color: var(--text-muted); font-size: 15px; }
.faq-answer-inner p { margin-bottom: 10px; }
.faq-answer-inner p:last-child { margin-bottom: 0; }
.faq-answer-inner ul { margin: 0 0 10px 20px; }

/* CARD LIST (hub pages, related links) */
.card-list { display: grid; gap: 14px; margin: 8px 0 32px; }
.card-link {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 18px 22px;
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.2s, background 0.2s;
}
.card-link:hover { border-color: rgba(59,130,246,0.35); background: var(--bg-card-hover); }
.card-link h3 { font-size: 17px; font-weight: 700; margin-bottom: 4px; }
.card-link p { font-size: 14px; color: var(--text-muted); }

/* CTA */
.cta-band {
  margin-top: 48px;
  background: linear-gradient(135deg, rgba(34,197,94,0.10), rgba(59,130,246,0.10));
  border: 1px solid rgba(34,197,94,0.25);
  border-radius: var(--radius);
  padding: 30px;
  text-align: center;
}
.cta-band h2 { font-size: 22px; font-weight: 750; letter-spacing: -0.5px; margin-bottom: 8px; }
.cta-band p { color: var(--text-muted); font-size: 15px; max-width: 520px; margin: 0 auto 18px; }
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: linear-gradient(135deg, var(--accent-green), #16A34A);
  color: #052e16;
  font-weight: 700;
  font-size: 15px;
  text-decoration: none;
  padding: 12px 22px;
  border-radius: 12px;
  transition: transform 0.15s, box-shadow 0.15s;
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 8px 24px rgba(34,197,94,0.25); }
.advisory-note {
  font-size: 13px;
  color: var(--text-dim);
  margin-top: 28px;
  border-top: 1px solid var(--border);
  padding-top: 16px;
}
.advisory-note a { color: var(--text-muted); }

/* FOOTER */
footer.site-footer {
  border-top: 1px solid var(--border);
  padding: 32px 40px;
  text-align: center;
}
.footer-links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px 24px;
  margin-bottom: 14px;
}
.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--text); }
.footer-copy { font-size: 13px; color: var(--text-dim); }

@media (max-width: 640px) {
  .nav-inner { padding: 0 20px; }
  .page-hero { padding: 48px 20px 40px; }
  .page-hero h1 { font-size: 30px; letter-spacing: -1px; }
  .page-wrap { padding: 40px 20px 72px; }
  .calc-grid { grid-template-columns: 1fr; }
  .prose h2 { font-size: 22px; }
  footer.site-footer { padding: 24px 20px; }
}

/* PRINT (worksheet pages) */
@media print {
  nav.site-nav, footer.site-footer, .cta-band, .no-print { display: none !important; }
  body { background: #fff; color: #111; font-size: 12pt; }
  .page-hero { background: #fff; border: none; padding: 0 0 12pt; text-align: left; }
  .page-hero h1 { color: #111; }
  .page-label, .page-sub { color: #444; -webkit-text-fill-color: #444; }
  .page-wrap { padding: 0; max-width: none; }
  .calc-card, .prose p.lede, .callout { background: #fff; border-color: #bbb; color: #111; }
  .calc-field input, .calc-field select { background: #fff; color: #111; border-color: #999; }
  .prose p, .prose li { color: #111; }
  a { color: #111; text-decoration: none; }
}