/* ============================================================
   NAV — FANUCAiLeadCV
   Sticky top navigation bar, mobile hamburger, active-section
   highlighting via IntersectionObserver (js/nav.js).
   ============================================================ */

/* ----------------------------------------------------------
   SITE HEADER — sticky container
---------------------------------------------------------- */

.site-header {
  position:   sticky;
  top:        0;
  z-index:    var(--z-sticky);
  background: rgba(10, 11, 15, 0.90);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: background-color var(--duration-base) var(--ease-out),
              border-color      var(--duration-base) var(--ease-out);
}

/* Scrolled state — added by nav.js when page scrolled > 60px */
.site-header--scrolled {
  background: rgba(10, 11, 15, 0.97);
  border-bottom-color: var(--color-border-strong);
}

/* ----------------------------------------------------------
   NAV INNER LAYOUT
---------------------------------------------------------- */

.site-nav__inner {
  display:         flex;
  align-items:     center;
  justify-content: space-between;
  height:          60px;
  gap:             var(--space-4);
}

/* ----------------------------------------------------------
   LOGO / MONOGRAM
---------------------------------------------------------- */

.site-nav__logo {
  display:     flex;
  align-items: center;
  flex-shrink: 0;
}

.site-nav__logo-text {
  font-size:      var(--text-lg);
  font-weight:    var(--font-bold);
  color:          var(--color-accent);
  letter-spacing: var(--tracking-wide);
  line-height:    1;
  transition:     color var(--duration-fast) var(--ease-out);
}

.site-nav__logo:hover .site-nav__logo-text,
.site-nav__logo:focus-visible .site-nav__logo-text {
  color: var(--color-accent-hover);
}

/* ----------------------------------------------------------
   DESKTOP NAV LIST
---------------------------------------------------------- */

.site-nav__list {
  display:     flex;
  align-items: center;
  gap:         var(--space-1);
  list-style:  none;
  flex:        1;
  justify-content: center;
}

.site-nav__link {
  display:       block;
  padding:       var(--space-2) var(--space-3);
  font-size:     var(--text-sm);
  font-weight:   var(--font-medium);
  color:         var(--color-text-secondary);
  border-radius: var(--radius-sm);
  transition:
    color            var(--duration-fast) var(--ease-out),
    background-color var(--duration-fast) var(--ease-out);
  white-space: nowrap;
  position:    relative;
}

.site-nav__link::after {
  content:          '';
  position:         absolute;
  bottom:           0;
  left:             50%;
  transform:        translateX(-50%) scaleX(0);
  width:            calc(100% - var(--space-6));
  height:           2px;
  background-color: var(--color-accent);
  border-radius:    var(--radius-full);
  transition:       transform var(--duration-fast) var(--ease-out);
  transform-origin: center;
}

.site-nav__link:hover,
.site-nav__link:focus-visible {
  color:            var(--color-text-primary);
  background-color: var(--color-bg-subtle);
}

/* Active section link — applied by nav.js via IntersectionObserver */
.site-nav__link.is-active {
  color: var(--color-accent);
}

.site-nav__link.is-active::after {
  transform: translateX(-50%) scaleX(1);
}

/* ----------------------------------------------------------
   DOWNLOAD CTA IN NAV (desktop)
---------------------------------------------------------- */

.site-nav__cta {
  flex-shrink: 0;
  font-size:   var(--text-xs);
  padding:     var(--space-2) var(--space-4);
}

/* ----------------------------------------------------------
   HAMBURGER BUTTON (mobile)
---------------------------------------------------------- */

.site-nav__hamburger {
  display:         flex;
  flex-direction:  column;
  justify-content: center;
  align-items:     center;
  gap:             5px;
  width:           40px;
  height:          40px;
  padding:         var(--space-2);
  border-radius:   var(--radius-sm);
  background:      transparent;
  border:          none;
  cursor:          pointer;
  flex-shrink:     0;
  transition:      background-color var(--duration-fast) var(--ease-out);
}

.site-nav__hamburger:hover,
.site-nav__hamburger:focus-visible {
  background-color: var(--color-bg-subtle);
}

.site-nav__hamburger-bar {
  display:          block;
  width:            20px;
  height:           2px;
  background-color: var(--color-text-primary);
  border-radius:    var(--radius-full);
  transition:
    transform        var(--duration-base) var(--ease-out),
    opacity          var(--duration-base) var(--ease-out),
    background-color var(--duration-fast) var(--ease-out);
  transform-origin: center;
}

/* Hamburger → X when open */
.site-nav__hamburger[aria-expanded="true"] .site-nav__hamburger-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.site-nav__hamburger[aria-expanded="true"] .site-nav__hamburger-bar:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.site-nav__hamburger[aria-expanded="true"] .site-nav__hamburger-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ----------------------------------------------------------
   MOBILE MENU PANEL
---------------------------------------------------------- */

.site-nav__mobile {
  border-top:    1px solid var(--color-border);
  background:    var(--color-bg-raised);
  padding-block: var(--space-4);
}

.site-nav__mobile ul {
  list-style: none;
  padding:    0;
  margin:     0;
}

.site-nav__mobile .site-nav__link {
  display:       block;
  padding:       var(--space-3) var(--space-6);
  font-size:     var(--text-base);
  border-radius: 0;
}

.site-nav__mobile .site-nav__link::after {
  display: none;
}

.site-nav__mobile .site-nav__link:hover,
.site-nav__mobile .site-nav__link:focus-visible {
  background-color: var(--color-bg-subtle);
  padding-left:     calc(var(--space-6) + var(--space-2));
}

.site-nav__mobile-cta {
  margin:    var(--space-4) var(--space-6) var(--space-2);
  width:     calc(100% - var(--space-12));
  justify-content: center;
}

/* ----------------------------------------------------------
   RESPONSIVE BREAKPOINTS
   Desktop nav list + CTA visible ≥ 768px.
   Hamburger visible < 768px.
---------------------------------------------------------- */

@media (max-width: 767px) {
  .site-nav__list,
  .site-nav__cta {
    display: none;
  }
}

@media (min-width: 768px) {
  .site-nav__hamburger {
    display: none;
  }
  .site-nav__mobile {
    display: none !important;
  }
}