/* ============================================
   HEADER / NAVIGATION COMPONENT
   Society & AI Design System
   ============================================

   Main site navigation including:
   - Desktop navigation
   - Mobile menu (hamburger)
   - Search dropdown
   - Scroll effects

   Requires: tokens.css to be loaded first
   ============================================ */

/* ==========================================
   HIDE HEXTRA DEFAULT NAV
   ========================================== */
.hextra-nav-container,
.hextra-navbar,
[class*="hextra"][class*="nav"] {
  display: none;
}

/* ==========================================
   CUSTOM NAVIGATION BASE
   ========================================== */
.custom-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--color-white);
  border-bottom: var(--border-width) solid var(--color-border);
  z-index: var(--z-fixed);
  height: var(--nav-height);
  transition: background var(--transition-slow),
              backdrop-filter var(--transition-slow),
              border-color var(--transition-slow),
              z-index 0s;
}

/* When mobile menu is open */
.custom-nav.menu-open {
  z-index: 1002;
  background: transparent;
  border-bottom-color: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
}

/* Scrolled state - translucent */
.custom-nav.scrolled {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: var(--border-width) solid rgba(224, 224, 224, 0.5);
}

/* ==========================================
   NAV CONTAINER
   ========================================== */
.nav-container {
  width: var(--content-width);
  max-width: var(--max-width-site);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 100%;
  padding: 0 var(--space-8);
  position: relative;
}

/* ==========================================
   LOGO / BRAND
   ========================================== */
.nav-brand {
  flex-shrink: 0;
  min-width: 200px;
  position: relative;
  z-index: 1003;
}

.nav-brand .logo-link {
  text-decoration: none;
  display: inline-block;
  color: var(--color-black);
  transition: color var(--transition-slow);
}

.nav-brand .logo-text {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: var(--font-semibold);
  color: var(--color-black);
  letter-spacing: -0.01em;
  white-space: nowrap;
  transition: color var(--transition-slow);
}

.nav-brand .ampersand {
  font-style: italic;
  font-family: var(--font-display);
  color: var(--color-black);
  transition: color var(--transition-slow);
}

/* Logo turns white when mobile menu is open */
.nav-brand.menu-open .logo-link,
.nav-brand.menu-open .logo-text,
.nav-brand.menu-open .ampersand {
  color: var(--color-white);
}

/* ==========================================
   DESKTOP NAVIGATION MENU
   ========================================== */
.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.nav-link {
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: var(--font-normal);
  color: var(--color-text);
  text-decoration: none;
  padding: var(--space-2) 0;
  transition: color var(--transition-base);
  background: none;
  border: none;
  cursor: pointer;
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

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

/* ==========================================
   SEARCH TOGGLE & DROPDOWN
   ========================================== */
.search-toggle {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.search-icon {
  width: 16px;
  height: 16px;
  stroke: currentColor;
}

.search-dropdown {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  width: 100%;
  background: var(--color-white);
  border-bottom: var(--border-width) solid var(--color-border);
  padding: var(--space-4) 0;
  box-shadow: var(--shadow-lg);
  transform: scaleY(0);
  transform-origin: top center;
  opacity: 0;
  visibility: hidden;
  transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1),
              opacity var(--transition-base),
              visibility 0.25s ease;
  z-index: var(--z-dropdown);
}

.search-dropdown.active {
  transform: scaleY(1);
  opacity: 1;
  visibility: visible;
}

.search-form {
  width: 100%;
  max-width: none;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0 var(--space-4);
}

.search-input-nav {
  flex: 1;
  padding: 0.875rem 1.25rem;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-xl);
  font-family: var(--font-body);
  font-size: var(--text-base);
  background: var(--color-bg-muted);
  transition: border-color var(--transition-base),
              background var(--transition-base);
}

.search-input-nav:focus {
  outline: none;
  border-color: var(--color-primary);
  background: var(--color-white);
}

.search-input-nav::placeholder {
  color: var(--color-text-muted);
}

.search-submit {
  padding: 0.875rem var(--space-4);
  background: var(--color-primary);
  border: none;
  border-radius: var(--radius-xl);
  color: var(--color-white);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition-base);
}

.search-submit:hover {
  background: var(--color-primary-dark);
}

/* ==========================================
   MOBILE MENU BUTTON (HAMBURGER)
   ========================================== */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
  width: 40px;
  height: 40px;
  position: relative;
  z-index: 10;
  touch-action: manipulation;
}

.mobile-menu-btn.menu-open {
  position: fixed;
  top: 12px;
  right: calc((100% - min(85%, 1680px)) / 2 + 1rem);
  z-index: 1002;
}

.hamburger-line {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-black);
  margin: 5px auto;
  transition: all var(--transition-slow);
  border-radius: 2px;
}

/* Hamburger to X Animation */
.mobile-menu-btn.menu-open .hamburger-line,
.mobile-menu-btn[aria-expanded="true"] .hamburger-line {
  background-color: var(--color-white);
}

.mobile-menu-btn.menu-open .hamburger-line:nth-child(1),
.mobile-menu-btn[aria-expanded="true"] .hamburger-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.mobile-menu-btn.menu-open .hamburger-line:nth-child(2),
.mobile-menu-btn[aria-expanded="true"] .hamburger-line:nth-child(2) {
  opacity: 0;
}

.mobile-menu-btn.menu-open .hamburger-line:nth-child(3),
.mobile-menu-btn[aria-expanded="true"] .hamburger-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ==========================================
   MOBILE MENU PANEL
   ========================================== */
.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-primary);
  z-index: 1001;
  overflow-y: auto;
  transform: translateY(-100%);
  opacity: 0;
  visibility: hidden;
  transition: transform 0.4s cubic-bezier(0.19, 1, 0.22, 1),
              opacity var(--transition-slow),
              visibility 0.4s ease;
  will-change: transform, opacity;
}

.mobile-menu.active {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

/* Close button inside mobile menu */
.mobile-menu-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 44px;
  height: 44px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 10px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  touch-action: manipulation;
}

.close-line {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-white);
  border-radius: 2px;
  position: absolute;
}

.close-line:first-child {
  transform: rotate(45deg);
}

.close-line:last-child {
  transform: rotate(-45deg);
}

.mobile-menu-content {
  padding: var(--space-8) var(--space-4);
  padding-top: 80px;
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  align-items: flex-end;
  text-align: right;
}

.mobile-menu-link {
  display: block;
  width: 100%;
  padding: 0.75rem 0;
  color: var(--color-white);
  text-decoration: none;
  font-family: var(--font-body);
  font-size: 1.4rem;
  font-weight: var(--font-medium);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  transition: opacity var(--transition-base),
              padding-right var(--transition-base);
}

.mobile-menu-link:hover {
  color: var(--color-white);
  opacity: 0.8;
  padding-right: var(--space-2);
}

/* ==========================================
   RESPONSIVE STYLES
   ========================================== */
@media (max-width: 968px) {
  .nav-menu {
    display: none;
  }

  .mobile-menu-btn {
    display: block;
  }
}

@media (max-width: 768px) {
  .nav-container {
    width: 100%;
    padding: 0 var(--space-4);
  }

  .nav-brand {
    min-width: auto;
  }

  .nav-brand .logo-text {
    font-size: 1.1rem;
  }

  .mobile-menu-btn.menu-open {
    right: var(--space-4);
  }
}

/* ==========================================
   MAIN CONTENT OFFSET
   ========================================== */
#main-content {
  min-height: calc(100vh - var(--nav-height));
}