/* ============================================================
   SKIP LINK — visually hidden, shown on focus (a11y)
============================================================ */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  background: var(--color-brand-primary);
  color: #fff;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  z-index: 9999;
  text-decoration: none;
  transition: top var(--dur-fast) var(--ease);
}
.skip-link:focus { top: var(--space-2); }

/* ============================================================
   BUTTONS
============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 500;
  line-height: 24px;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--dur-fast) var(--ease);
  white-space: nowrap;
}
.btn:active { transform: scale(0.98); }
.btn:focus-visible { box-shadow: var(--shadow-focus); outline: none; }
.btn:disabled { opacity: 0.4; pointer-events: none; }

.btn-lg {
  height: 48px;
  padding: 0 var(--space-5);
  border-radius: var(--radius-md);
  font-size: 16px;
}

.btn-md {
  height: 40px;
  padding: 0 var(--space-4);
  border-radius: var(--radius-md);
}

.btn-sm {
  height: 32px;
  padding: 0 var(--space-3);
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 500;
}

.btn-primary {
  background: var(--color-brand-action);
  color: #fff;
  box-shadow: var(--shadow-brand);
}
.btn-primary:hover {
  background: var(--color-brand-action-hover);
  color: #fff;
  box-shadow: 0 6px 20px rgba(0,157,100,.35);
}

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-brand-primary);
  border: 1.5px solid var(--color-border-strong);
  box-shadow: var(--shadow-sm);
}
.btn-secondary:hover {
  background: var(--color-hover-overlay);
  color: var(--color-brand-primary);
}

.btn-ghost {
  background: transparent;
  color: var(--color-brand-primary);
}
.btn-ghost:hover {
  background: var(--color-hover-overlay);
  color: var(--color-brand-primary);
}

.btn-ghost-inv {
  background: transparent;
  color: rgba(255,255,255,.85);
  border: 1.5px solid rgba(255,255,255,.25);
}
.btn-ghost-inv:hover {
  background: rgba(255,255,255,.08);
  color: #fff;
  border-color: rgba(255,255,255,.5);
}

.btn-oauth {
  background: #24292f;
  color: #fff;
  border: 1.5px solid #444;
  gap: var(--space-2);
}
.btn-oauth:hover {
  background: #2f363d;
  color: #fff;
  border-color: #555;
}

/* ============================================================
   NAVIGATION
============================================================ */
header {
  position: sticky;
  top: 0;
  z-index: 200;
}

.nav {
  height: var(--nav-height);
  display: flex;
  align-items: center;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background-color: rgba(255, 255, 255, 0.85);
}

.nav > .container { height: 100%; }

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: var(--space-6);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--color-brand-primary);
  text-decoration: none;
  flex-shrink: 0;
}
.nav-logo:hover { color: var(--color-brand-primary); }

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  flex: 1;
  justify-content: center;
}

.nav-link {
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 500;
  line-height: 1;
  color: var(--color-ink-base);
  text-decoration: none;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  transition: color var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}
.nav-link:hover {
  color: var(--color-brand-action);
  background: var(--color-success-bg);
}

.nav-link.active { color: var(--color-brand-action); background: var(--color-success-bg); }

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}

.nav-signin {
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 500;
  color: var(--color-ink-base);
  text-decoration: none;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  transition: color var(--dur-fast) var(--ease);
}
.nav-signin:hover { color: var(--color-brand-action); }

/* Hamburger */
.nav-hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
  border-radius: var(--radius-sm);
  transition: background var(--dur-fast) var(--ease);
  flex-shrink: 0;
}
.nav-hamburger:hover { background: var(--color-surface-raised); }
.nav-hamburger:focus-visible { box-shadow: var(--shadow-focus); outline: none; }

.nav-hamburger span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-ink-base);
  border-radius: 2px;
  transition: all var(--dur-base) var(--ease);
  transform-origin: center;
}

.nav-hamburger[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-hamburger[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.nav-hamburger[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile nav drawer */
.nav-mobile {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-lg);
  z-index: 190;
  padding: var(--space-4) var(--space-4) var(--space-5);
}

.nav-mobile.is-open { display: block; }

.nav-mobile-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  margin-bottom: var(--space-5);
}

.nav-mobile-link {
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 500;
  color: var(--color-ink-base);
  text-decoration: none;
  padding: var(--space-3) 0;
  border-radius: var(--radius-sm);
  border-bottom: 1px solid var(--color-border);
}
.nav-mobile-link:last-child { border-bottom: none; }
.nav-mobile-link:hover { color: var(--color-brand-action); }

.nav-mobile-actions {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-signin { display: none; }
  .nav-cta { display: none; }
  .nav-hamburger { display: flex; }
  .nav-actions { gap: var(--space-2); }
  .site-nav .container { padding: 0 var(--space-3); }
}

/* ============================================================
   HERO
============================================================ */
.hero {
  padding: var(--space-12) 0 var(--space-10);
  text-align: center;
  overflow: hidden;
  position: relative;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.6; transform: scale(0.8); }
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(36px, 5.5vw, 64px);
  line-height: 1.1;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--color-ink-strong);
  max-width: 14ch;
  margin: 0 auto;
}

.hero-title .accent {
  color: var(--color-brand-action);
}

.hero-sub {
  font-family: var(--font-body);
  font-size: 20px;
  line-height: 32px;
  color: var(--color-ink-muted);
  max-width: 46ch;
  margin: var(--space-5) auto 0;
}

.hero-actions {
  display: flex;
  gap: var(--space-3);
  justify-content: center;
  flex-wrap: wrap;
  margin-top: var(--space-8);
}

/* Hero flight path decoration - SVG only, no emoji */
.hero-visual {
  margin: var(--space-6) auto 0;
  max-width: 760px;
  position: relative;
}

/* SVG flight path illustration placeholder */
.hero-flightpath {
  width: 100%;
  display: block;
  max-height: 60px;
}

@media (max-width: 639px) {
  .hero {
    padding: var(--space-10) 0 var(--space-8);
  }
  .hero-sub {
    font-size: 17px;
    line-height: 28px;
  }
  .hero-actions {
    flex-direction: column;
    align-items: center;
  }
  .hero-visual {
    margin-top: var(--space-7);
  }
}

/* ============================================================
   TRUST BAR
============================================================ */
.trust-bar-section {
  padding: var(--space-4) 0 var(--space-9);
}

.trust-divider {
  width: 100%;
  height: 1px;
  background: var(--color-border);
  margin-bottom: var(--space-9);
}

.trust-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-5);
}

.trust-stat {
  text-align: center;
  padding: var(--space-4);
}

.trust-stat-value {
  font-family: var(--font-display);
  font-size: 38px;
  line-height: 48px;
  font-weight: 700;
  color: var(--color-brand-action);
  letter-spacing: -0.02em;
  display: block;
}

.trust-stat-label {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 22px;
  color: var(--color-ink-muted);
  margin-top: var(--space-1);
  display: block;
}

@media (max-width: 768px) {
  .trust-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
  }
}

@media (max-width: 479px) {
  .trust-bar { grid-template-columns: 1fr 1fr; }
  .trust-stat-value { font-size: 28px; }
}

/* ============================================================
   VALUE PROPS
============================================================ */
.section {
  padding: var(--space-10) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-9);
}

.section-label {
  display: inline-block;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-brand-action);
  margin-bottom: var(--space-3);
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(28px, 3.5vw, 38px);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--color-ink-strong);
}

.section-sub {
  font-family: var(--font-body);
  font-size: 18px;
  line-height: 30px;
  color: var(--color-ink-muted);
  max-width: 52ch;
  margin: var(--space-4) auto 0;
}

/* Feature cards grid */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-5);
}

/* Opaque card backgrounds */
.card,
.feature-card,
.path-card {
  background: #FFFFFF;
}

.feature-card {
  border-radius: var(--radius-xl);
  padding: var(--space-8) var(--space-6);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--color-border);
  transition: box-shadow var(--dur-base) var(--ease), transform var(--dur-base) var(--ease);
}

.feature-card:hover {
  box-shadow: var(--shadow-xl);
  transform: translateY(-3px);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin-bottom: var(--space-5);
  display: block;
  flex-shrink: 0;
}

.feature-card h3 {
  font-size: 22px;
  line-height: 30px;
  margin-bottom: var(--space-3);
}

.feature-card p {
  font-size: 16px;
  line-height: 26px;
  color: var(--color-ink-muted);
  max-width: none;
}

.feature-detail {
  margin-top: var(--space-5);
  padding-top: var(--space-5);
  border-top: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.feature-detail-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: 14px;
  color: var(--color-ink-base);
}

.feature-check {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

@media (max-width: 1023px) {
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 639px) {
  .feature-grid { grid-template-columns: 1fr; }
  .feature-card { padding: var(--space-6) var(--space-5); }
}

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
  background: #001A24;
  color: rgba(255,255,255,.75);
  padding: var(--space-10) 0 var(--space-6);
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-8);
  padding-bottom: var(--space-8);
  border-bottom: 1px solid rgba(255,255,255,.08);
}
.footer-brand-name {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: #fff;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-3);
}
.footer-brand-desc {
  font-size: 14px;
  line-height: 22px;
  color: rgba(255,255,255,.5);
  max-width: 32ch;
}
.footer-col-heading {
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(255,255,255,.4);
  margin-bottom: var(--space-4);
}
.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}
.footer-link {
  font-size: 14px;
  line-height: 22px;
  color: rgba(255,255,255,.65);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease);
  padding: var(--space-1) 0;
}
.footer-link:hover { color: #fff; }
.footer-link:focus-visible {
  outline: none;
  box-shadow: var(--shadow-focus);
  border-radius: var(--radius-xs);
}
.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding-top: var(--space-5);
  flex-wrap: wrap;
}
.footer-copy {
  font-size: 13px;
  color: rgba(255,255,255,.35);
}
.footer-status {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--primitive-green-500);
  text-decoration: none;
}
.status-dot {
  width: 7px;
  height: 7px;
  background: var(--primitive-green-500);
  border-radius: 50%;
  box-shadow: 0 0 0 0 rgba(0,192,122,.4);
  animation: ping 2.5s ease-in-out infinite;
}
@keyframes ping {
  0%   { box-shadow: 0 0 0 0 rgba(0,192,122,.5); }
  70%  { box-shadow: 0 0 0 6px rgba(0,192,122,0); }
  100% { box-shadow: 0 0 0 0 rgba(0,192,122,0); }
}
@media (max-width: 1023px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand-wrap { grid-column: 1 / -1; }
}
@media (max-width: 639px) {
  .footer-grid { grid-template-columns: 1fr; gap: var(--space-6); }
  .footer-brand-wrap { grid-column: 1; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

/* Mobile tap targets */
.footer-link, .footer a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

/* ============================================================
   THEME TOGGLE + DARK MODE NAV
   ============================================================ */

/* ============================================================
   SCREEN READER ONLY
   ============================================================ */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

/* ============================================================
   THEME TOGGLE
   ============================================================ */