/* ═══════════════════════════════════════════════════════════
   ORGANISM: Site Header
   Logo + primary nav with dropdowns + CTA button + theme toggle
   Sticky on scroll, blur backdrop, mobile hamburger
   ═══════════════════════════════════════════════════════════ */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: var(--z-sticky);
  background: rgba(6, 11, 20, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-rule);
  transition: background-color 0.2s ease;
}

[data-theme="light"] .site-header {
  background: rgba(248, 250, 252, 0.92);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .site-header {
    background: rgba(248, 250, 252, 0.92);
  }
}


/* ── Inner layout ────────────────────────────────────────── */

.site-header__inner {
  max-width: var(--max-width-page);
  margin: 0 auto;
  height: 100%;
  display: flex;
  align-items: center;
  padding: 0;
  gap: var(--space-6);
}


/* ── Logo ────────────────────────────────────────────────── */

.site-header__logo {
  display: inline-flex;
  align-items: baseline;
  font-family: var(--font-heading);
  font-size: var(--text-5xl);
  font-weight: var(--weight-extrabold);
  color: var(--color-text-1);
  text-decoration: none;
  line-height: var(--leading-none);
  flex-shrink: 0;
}

.site-header__logo .fk-f { letter-spacing: 0; color: var(--color-blue); }
.site-header__logo .fk-c { letter-spacing: 0; margin-left: 0.02em; color: var(--color-blue-mid); }
.site-header__logo .fk-i { letter-spacing: 0; margin-left: 0.05em; color: var(--color-sky); }


/* ── Desktop navigation ──────────────────────────────────── */

.site-header__nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  margin-left: var(--space-8);
  flex: 1;
}

.site-header__nav-item {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  color: var(--color-text-2);
  text-decoration: none;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color 0.15s ease, background-color 0.15s ease;
  background: none;
  border: none;
}

.site-header__nav-item:hover {
  color: var(--color-text-1);
  background: var(--color-surface-hover);
}

.site-header__nav-item.is-active {
  color: var(--color-sky);
  font-weight: var(--weight-semibold);
}

/* Active item inside a desktop dropdown */
.site-header__dropdown-link.is-active {
  color: var(--color-sky);
  background: rgba(14, 165, 233, 0.08);
}


/* ── Dropdown caret ──────────────────────────────────────── */

.site-header__caret {
  display: inline-block;
  width: 8px;
  height: 8px;
  position: relative;
  transition: transform 0.2s ease;
}

.site-header__caret::after {
  content: "";
  display: block;
  width: 5px;
  height: 5px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg);
  position: absolute;
  top: 0;
  left: 1px;
  opacity: 0.5;
}

.site-header__nav-item:hover .site-header__caret::after {
  opacity: 1;
}


/* ── Dropdown panel ──────────────────────────────────────── */

.site-header__dropdown {
  position: absolute;
  top: calc(100% + 4px);
  left: 0;
  min-width: 240px;
  background: var(--color-surface);
  border: 1px solid var(--color-rule);
  border-radius: var(--radius-lg);
  padding: var(--space-2);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity 0.15s ease, transform 0.15s ease, visibility 0.15s;
  z-index: var(--z-dropdown);
}

.site-header__nav-item:hover .site-header__dropdown,
.site-header__nav-item[aria-expanded="true"] .site-header__dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.site-header__nav-item[aria-expanded="true"] .site-header__caret {
  transform: rotate(180deg);
}

.site-header__dropdown-link {
  display: block;
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-base);
  font-weight: var(--weight-regular);
  color: var(--color-text-2);
  text-decoration: none;
  text-align: left;
  border-radius: var(--radius-sm);
  transition: background-color 0.1s ease, color 0.1s ease;
}

.site-header__dropdown-link:hover {
  background: var(--color-surface-hover);
  color: var(--color-text-1);
}


/* ── Mega dropdown (Solutions) ───────────────────────────── */

.site-header__dropdown--mega {
  min-width: 420px;
  left: 50%;
  transform: translateX(-50%) translateY(6px);
}

.site-header__nav-item:hover .site-header__dropdown--mega,
.site-header__nav-item[aria-expanded="true"] .site-header__dropdown--mega {
  transform: translateX(-50%) translateY(0);
}

.site-header__mega-title {
  text-align: center;
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  color: var(--color-text-3);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: var(--space-2) var(--space-3) var(--space-1);
  border-bottom: 1px solid var(--color-rule);
  margin-bottom: var(--space-1);
}

.site-header__mega-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0 var(--space-2);
}

.site-header__mega-col {
  display: flex;
  flex-direction: column;
}


/* ── Right-side actions ──────────────────────────────────── */

.site-header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-left: auto;
  flex-shrink: 0;
}


/* ── Theme toggle ────────────────────────────────────────── */

.site-header__theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: none;
  border: 1px solid var(--color-rule);
  border-radius: var(--radius-sm);
  cursor: pointer;
  color: var(--color-text-3);
  font-size: var(--text-lg);
  transition: color 0.15s ease, border-color 0.15s ease, background-color 0.15s ease;
  padding: 0;
  line-height: 1;
}

.site-header__theme-toggle:hover {
  color: var(--color-text-1);
  border-color: var(--color-text-3);
  background: var(--color-surface-hover);
}


/* ── Hamburger button (mobile) ───────────────────────────── */

.site-header__hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  gap: 5px;
}

.site-header__hamburger-line {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-text-2);
  border-radius: 1px;
  transition: transform 0.25s ease, opacity 0.15s ease;
}

/* Animated X when open */
.site-header__hamburger.is-open .site-header__hamburger-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.site-header__hamburger.is-open .site-header__hamburger-line:nth-child(2) {
  opacity: 0;
}

.site-header__hamburger.is-open .site-header__hamburger-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}


/* ── Mobile menu overlay ─────────────────────────────────── */

.site-header__mobile-menu {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-bg);
  border-top: 1px solid var(--color-rule);
  padding: var(--space-6) var(--space-6) var(--space-12);
  overflow-y: auto;
  z-index: var(--z-overlay);
  opacity: 0;
  transform: translateY(-8px);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.site-header__mobile-menu.is-open {
  display: block;
  opacity: 1;
  transform: translateY(0);
}

.site-header__mobile-section {
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-rule);
}

.site-header__mobile-section:last-child {
  border-bottom: none;
}

.site-header__mobile-section-title {
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-widest);
  text-transform: uppercase;
  color: var(--color-text-3);
  padding: var(--space-2) var(--space-3);
}

.site-header__mobile-section-subtitle {
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  color: var(--color-text-3);
  padding: 0 var(--space-3) var(--space-1);
}

.site-header__mobile-link {
  display: block;
  padding: var(--space-3) var(--space-3);
  font-size: var(--text-lg);
  font-weight: var(--weight-medium);
  color: var(--color-text-1);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: background-color 0.1s ease;
}

.site-header__mobile-link:hover {
  background: var(--color-surface-hover);
}

.site-header__mobile-sub-link {
  display: block;
  padding: var(--space-2) var(--space-3) var(--space-2) var(--space-6);
  font-size: var(--text-base);
  font-weight: var(--weight-regular);
  color: var(--color-text-2);
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: background-color 0.1s ease, color 0.1s ease;
}

.site-header__mobile-sub-link:hover {
  background: var(--color-surface-hover);
  color: var(--color-text-1);
}

.site-header__mobile-link.is-active {
  color: var(--color-sky);
}

.site-header__mobile-sub-link.is-active {
  color: var(--color-sky);
}


/* ── Scroll lock when mobile menu is open ───────────────── */
/* Applied via classList — no inline style mutation */
body.nav-open {
  overflow: hidden;
}


/* ── Mobile breakpoint ───────────────────────────────────── */

@media (max-width: 768px) {
  .site-header__inner {
    padding: 0 var(--space-4);
  }

  .site-header__nav {
    display: none;
  }

  .site-header__hamburger {
    display: flex;
  }

  /* Hide CTA buttons and portal on mobile (they're in the mobile menu) */
  .site-header__actions .btn,
  .site-header__actions .nav-portal {
    display: none;
  }
}


/* ── FCI Portal Login (split button) ───────────────────── */

.nav-portal {
  display: inline-flex;
  align-items: center;
  gap: 0;
  text-decoration: none;
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-wide);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s;
}

.nav-portal {
  margin-right: var(--space-2);
}

.nav-portal:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(14, 165, 233, 0.25);
  color: inherit;
}

.nav-portal__label {
  padding: 4px 12px;
  color: var(--color-text-2);
  background: var(--color-surface-2);
  border: 1px solid var(--color-rule);
  border-right: none;
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  transition: color 0.15s ease, background 0.15s ease;
}

.nav-portal:hover .nav-portal__label {
  color: var(--color-text-1);
  background: var(--color-surface);
}

.nav-portal__login {
  padding: 4px 14px 4px 12px;
  color: var(--color-white);
  background: linear-gradient(135deg, var(--color-sky), var(--color-blue));
  border: 1px solid rgba(14, 165, 233, 0.4);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  transition: background 0.15s ease;
}

.nav-portal__arrow {
  display: inline-block;
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.nav-portal:hover .nav-portal__arrow {
  transform: translateX(3px);
}