/* ============================================
   HEADER + NAVIGATION
   ============================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in oklab, var(--color-bg), transparent 10%);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow var(--transition-smooth), background var(--transition-smooth);
}

.site-header--scrolled {
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  height: 64px;
}

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-primary);
  flex-shrink: 0;
}

.site-logo__mark {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
}

.site-logo__text {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text);
  line-height: 1.2;
}

/* Nav */
.site-nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  margin-left: auto;
}

.site-nav a {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: color var(--transition-interactive), background var(--transition-interactive);
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--color-text);
  background: var(--color-surface-offset);
}

/* Header CTA */
.header-cta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-left: var(--space-4);
}

/* Theme Toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  background: transparent;
  cursor: pointer;
  flex-shrink: 0;
}

.theme-toggle:hover {
  color: var(--color-text);
  background: var(--color-surface-offset);
  border-color: var(--color-border);
}

/* Mobile menu toggle */
.mobile-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  color: var(--color-text);
  cursor: pointer;
  background: none;
  border: none;
  margin-left: auto;
}

@media (max-width: 768px) {
  .site-nav,
  .header-cta .btn {
    display: none;
  }

  .mobile-toggle {
    display: flex;
  }

  .header-cta {
    margin-left: auto;
  }

  .site-nav.is-open {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--color-bg);
    padding: var(--space-8) var(--space-6);
    gap: var(--space-2);
    z-index: 99;
    border-top: 1px solid var(--color-border);
    overflow-y: auto;
  }

  .site-nav.is-open a {
    font-size: var(--text-base);
    padding: var(--space-4) var(--space-4);
    border-radius: var(--radius-md);
    border-bottom: 1px solid var(--color-divider);
  }

  .header-inner {
    position: relative;
  }
}

/* ============================================
   FOOTER
   ============================================ */

.site-footer {
  background: var(--color-surface-offset-2);
  border-top: 1px solid var(--color-border);
  padding-block: clamp(var(--space-12), 6vw, var(--space-20));
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr 1fr;
  gap: var(--space-10);
  margin-bottom: var(--space-12);
}

.footer-brand {
  grid-column: 1;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--color-primary);
  text-decoration: none;
  margin-bottom: var(--space-4);
}

.footer-tagline {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.6;
  max-width: 28ch;
  margin-bottom: var(--space-6);
}

.footer-signup .email-form {
  flex-direction: column;
}

.footer-signup .email-form input[type="email"] {
  border-color: var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  min-width: unset;
}

.footer-signup .email-form input[type="email"]::placeholder {
  color: var(--color-text-faint);
}

.footer-signup .email-form input[type="email"]:focus {
  border-color: var(--color-primary);
  background: var(--color-surface-2);
}

.footer-nav h4 {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.footer-nav ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-nav a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  line-height: 1.5;
}

.footer-nav a:hover {
  color: var(--color-primary);
}

.footer-bottom {
  border-top: 1px solid var(--color-divider);
  padding-top: var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}

.footer-disclosure {
  max-width: 60ch;
}

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-8);
  }

  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 600px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}