/* =====================================================================
   Unbuilt Lab — Unified site header
   Single source of truth. Loaded via <link> on every page.
   2026-05-06
   ===================================================================== */

:root {
  --ul-nav-bg: rgba(10, 10, 15, 0.85);
  --ul-nav-border: rgba(99, 102, 241, 0.10);
  --ul-nav-accent: #6366f1;
  --ul-nav-accent-soft: rgba(99, 102, 241, 0.12);
  --ul-nav-accent-secondary: #a78bfa;
  --ul-nav-accent-glow: rgba(99, 102, 241, 0.3);
  --ul-nav-text-primary: #f0f0f5;
  --ul-nav-text-secondary: #9a9ab0;
  --ul-nav-font-body: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
}

.ul-nav {
  position: sticky; top: 0; z-index: 100;
  background: var(--ul-nav-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--ul-nav-border);
  padding: 16px 0;
  font-family: var(--ul-nav-font-body);
}

.ul-nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.ul-nav .nav-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: 'Inter', -apple-system, sans-serif;
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--ul-nav-text-primary);
  text-decoration: none;
  white-space: nowrap;
  flex-shrink: 0;
}
.ul-nav .nav-logo img {
  width: 36px; height: 36px; border-radius: 8px;
  flex-shrink: 0;
}

.ul-nav .nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
  justify-content: center;
}
.ul-nav .nav-links a:not(.nav-cta) {
  font-family: var(--ul-nav-font-body);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--ul-nav-text-secondary);
  letter-spacing: 0.005em;
  padding: 9px 14px;
  border-radius: 8px;
  text-decoration: none;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: background 0.2s ease, color 0.2s ease;
}
.ul-nav .nav-links a:not(.nav-cta):hover {
  color: var(--ul-nav-text-primary);
  background: var(--ul-nav-accent-soft);
}
.ul-nav .nav-links a.active:not(.nav-cta) {
  color: var(--ul-nav-text-primary);
  background: rgba(99, 102, 241, 0.18);
}
.ul-nav .nav-links a.nav-pdf { color: var(--ul-nav-accent-secondary); }
.ul-nav .nav-links a.nav-pdf:hover { color: #fff; }

/* UL-013: free AI tool nav link — slightly more prominent than nav-pdf
   since it's the headline lead magnet. Faint accent pill so the eye
   catches it without screaming "BUY NOW". */
.ul-nav .nav-links a.nav-tool {
  color: var(--ul-nav-accent-primary, #6366f1);
  background: rgba(99, 102, 241, 0.10);
  font-weight: 600;
}
.ul-nav .nav-links a.nav-tool:hover {
  background: rgba(99, 102, 241, 0.22);
  color: #fff;
}

.ul-nav .nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: 50px;
  background: var(--ul-nav-accent);
  color: #fff;
  font-family: var(--ul-nav-font-body);
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  flex-shrink: 0;
  transition: transform 0.2s, box-shadow 0.2s;
}
.ul-nav .nav-cta:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 24px var(--ul-nav-accent-glow);
}

.ul-mobile-toggle {
  display: none;
  background: none; border: none; cursor: pointer; padding: 4px;
}
.ul-mobile-toggle span {
  display: block; width: 22px; height: 2px;
  background: var(--ul-nav-text-secondary);
  margin: 5px 0;
  transition: all 0.3s;
}

.ul-nav .nav-cta-mobile { display: none; }

/* Mobile breakpoint */
@media (max-width: 900px) {
  .ul-nav .nav-cta-desktop { display: none; }
  .ul-nav .nav-links {
    display: none;
    position: absolute; top: 100%; left: 0; right: 0;
    /* Differentiated panel bg (slightly lighter than body #0a0a0f) */
    background: linear-gradient(180deg, rgba(28, 28, 42, 0.985), rgba(22, 22, 34, 0.985));
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    flex-direction: column;
    padding: 8px;
    gap: 0;
    border-top: 1px solid rgba(99, 102, 241, 0.30);
    border-bottom: 1px solid rgba(99, 102, 241, 0.18);
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.45);
  }
  .ul-nav .nav-links.open { display: flex; }
  .ul-nav .nav-links a:not(.nav-cta) {
    width: 100%;
    border-radius: 6px;
    padding: 14px 14px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.18);
  }
  .ul-nav .nav-links a:not(.nav-cta):last-of-type { border-bottom: none; }
  .ul-nav .nav-links a:not(.nav-cta):hover {
    background: rgba(99, 102, 241, 0.16);
  }
  .ul-nav .nav-cta-mobile {
    display: inline-flex;
    width: 100%; justify-content: center;
    margin-top: 8px;
  }
  .ul-mobile-toggle { display: block; }
}

@media (max-width: 480px) {
  .ul-nav-container { padding: 0 16px; }
  .ul-nav .nav-logo { font-size: 1.15rem; }
  .ul-nav .nav-logo img { width: 32px; height: 32px; }
}