/* FILE: assets/css/navbar.css (UPDATED FULL VERSION) */
/* =============================================================================
   NAVIGATION BAR
   Fixed Z-Index Stacking to prevent "Blurry/Unclickable" menu
   ============================================================================= */

/* 1. HEADER (Container) */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 72px;

  /* Layer 2: Above content and overlay */
  z-index: 1000;

  background-color: var(--white);
  border-bottom: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);

  display: flex;
  align-items: center;
  transition: all 0.3s ease;
}

/* Progress indicator bar */
.site-header::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  height: 3px;
  width: var(--scroll-progress, 0%);
  background: linear-gradient(
    90deg,
    var(--primary-color),
    var(--primary-light)
  );
  transition: width 0.1s ease-out;
}

.site-header.scrolled {
  background-color: rgba(255, 255, 255, 0.98);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

/* Dark Mode Header */
body.dark-mode .site-header {
  background-color: var(--background-light);
  border-bottom-color: var(--gray-200);
}

body.dark-mode .site-header.scrolled {
  background-color: rgba(15, 23, 42, 0.98);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

/* -----------------------------------------------------------------------------
   NAVIGATION LAYOUT
   ----------------------------------------------------------------------------- */
.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  height: 100%;
}

/* Logo */
.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-dark);
  text-decoration: none;
  z-index: 1002;
}

.navbar-brand:hover {
  color: var(--primary-color);
}

/* Desktop Menu */
.navbar-menu {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  list-style: none;
  margin: 0;
  padding: 0;
}

.navbar-menu a {
  font-size: 1rem;
  font-weight: 500;
  color: var(--gray-600);
  text-decoration: none;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast);
  position: relative;
}

/* Underline animation for nav links */
.navbar-menu a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0.75rem;
  right: 0.75rem;
  height: 2px;
  background: linear-gradient(
    90deg,
    var(--primary-color),
    var(--primary-light)
  );
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.3s ease;
  border-radius: 2px;
}

.navbar-menu a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.navbar-menu a:hover {
  color: var(--primary-color);
}

.navbar-menu a.active {
  color: var(--primary-color);
  font-weight: 600;
}

.navbar-menu a.active::after {
  transform: scaleX(1);
}

/* Focus styles for keyboard navigation */
.navbar-menu a:focus-visible {
  outline: 2px solid var(--focus-ring, var(--primary-color));
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.navbar-toggle:focus-visible {
  outline: 2px solid var(--focus-ring, var(--primary-color));
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.navbar-social a:focus-visible {
  outline: 2px solid var(--focus-ring, var(--primary-color));
  outline-offset: 2px;
  border-radius: 50%;
}

/* 2. MOBILE MENU OVERLAY (Backdrop) - Sits BEHIND the header */
.navbar-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;

  /* Layer 1: Above page content, but BELOW header/menu */
  z-index: 900;

  background-color: rgba(0, 0, 0, 0.6);
  /* Removing backdrop-filter fixed the "blurry non-clickable" bug on some devices */

  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

.navbar-overlay.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

/* 3. MOBILE MENU TOGGLE (Layer 4 - Topmost) */
.navbar-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  width: 44px;
  height: 44px;
  padding: 0;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: 1002;
}

.navbar-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--text-dark);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.navbar-toggle.active span:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}
.navbar-toggle.active span:nth-child(2) {
  opacity: 0;
}
.navbar-toggle.active span:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* 4. MOBILE DRAWER (Layer 3) */
@media (max-width: 992px) {
  .navbar-toggle {
    display: flex;
  }

  .navbar-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 85%;
    max-width: 320px;
    height: 100vh;

    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;

    background-color: var(--white);
    padding: 100px 24px 40px;
    box-shadow: -5px 0 30px rgba(0, 0, 0, 0.2);

    transition: right 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 1001; /* Above header base, below toggle */
    overflow-y: auto;
  }

  .navbar-menu.active {
    right: 0;
  }

  .navbar-menu li {
    width: 100%;
    border-bottom: 1px solid var(--gray-200);
    opacity: 0;
    transform: translateX(20px);
    transition: opacity 0.3s ease, transform 0.3s ease;
  }

  .navbar-menu.active li {
    opacity: 1;
    transform: translateX(0);
  }

  /* Staggered animation for menu items */
  .navbar-menu.active li:nth-child(1) {
    transition-delay: 0.05s;
  }
  .navbar-menu.active li:nth-child(2) {
    transition-delay: 0.1s;
  }
  .navbar-menu.active li:nth-child(3) {
    transition-delay: 0.15s;
  }
  .navbar-menu.active li:nth-child(4) {
    transition-delay: 0.2s;
  }
  .navbar-menu.active li:nth-child(5) {
    transition-delay: 0.25s;
  }
  .navbar-menu.active li:nth-child(6) {
    transition-delay: 0.3s;
  }
  .navbar-menu.active li:nth-child(7) {
    transition-delay: 0.35s;
  }
  .navbar-menu.active li:nth-child(8) {
    transition-delay: 0.4s;
  }
  .navbar-menu.active li:nth-child(9) {
    transition-delay: 0.45s;
  }

  .navbar-menu a {
    display: block;
    padding: 1rem 0;
    font-size: 1.1rem;
    width: 100%;
    min-height: 44px; /* WCAG touch target */
    display: flex;
    align-items: center;
  }

  /* Remove underline animation on mobile */
  .navbar-menu a::after {
    display: none;
  }

  .navbar-menu a.active {
    color: var(--primary-color);
    background: linear-gradient(90deg, rgba(90, 31, 153, 0.08), transparent);
    padding-left: 1rem;
    margin-left: -1rem;
    border-left: 3px solid var(--primary-color);
  }

  /* Social Icons Mobile */
  .navbar-social {
    width: 100%;
    margin: 2rem 0 0 0;
    padding: 1.5rem 0 0 0;
    border-left: none;
    border-top: 1px solid var(--gray-200);
    justify-content: center;
  }

  body.dark-mode .navbar-menu {
    background-color: var(--background-light);
  }
}

/* Social Icons Desktop */
.navbar-social {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-left: var(--space-4);
  padding-left: var(--space-4);
  border-left: 1px solid var(--gray-300);
}

.navbar-social a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  color: var(--gray-600);
  transition: all var(--transition-fast);
}

.navbar-social a:hover {
  color: var(--primary-color);
  transform: translateY(-2px);
}

.navbar-social svg {
  width: 20px;
  height: 20px;
}
body.menu-open {
  overflow: hidden;
}