/* ============================================================
   CallD.AI — Navigation Component
   Sticky nav, mega-dropdown, backdrop blur, mobile hamburger
   ============================================================ */

/* ── Site header ── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-sticky);
  padding-block: var(--sp-4);
  background-color: rgba(245, 240, 235, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid transparent;
  transition: background-color 0.3s ease, border-color 0.3s ease, padding 0.3s ease;
}

.site-header.is-scrolled {
  padding-block: var(--sp-3);
  border-bottom-color: var(--c-border-subtle);
  box-shadow: var(--shadow-nav);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-w-wide);
  margin-inline: auto;
  padding-inline: var(--content-pad);
}

/* ── Logo ── */
.site-header__logo {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  flex-shrink: 0;
}

.site-header__logo img,
.site-header__logo svg {
  height: 32px;
  width: auto;
}

.site-header__logo-text {
  font-family: var(--f-serif);
  font-size: var(--fs-lg);
  font-weight: var(--fw-bold);
  color: var(--c-ink);
  letter-spacing: -0.01em;
}

.site-header__logo-text span {
  color: var(--c-green);
}

/* ── Main nav links ── */
.nav {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
}

.nav__item {
  position: relative;
}

.nav__link {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
  padding: var(--sp-2) var(--sp-3);
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  color: var(--c-body);
  border-radius: var(--r-md);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.nav__link:hover,
.nav__link[aria-expanded="true"] {
  color: var(--c-ink);
  background-color: rgba(27, 107, 82, 0.06);
}

/* Chevron icon for dropdowns */
.nav__chevron {
  width: 12px;
  height: 12px;
  transition: transform var(--transition-fast);
}

.nav__link[aria-expanded="true"] .nav__chevron {
  transform: rotate(180deg);
}

/* ── Mega dropdown ── */
.nav__dropdown {
  position: absolute;
  top: calc(100% + var(--sp-2));
  left: 50%;
  transform: translateX(-50%);
  min-width: 520px;
  background-color: var(--c-white);
  border: 1px solid var(--c-border-subtle);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-lg);
  padding: var(--sp-6);
  opacity: 0;
  visibility: hidden;
  transform: translateX(-50%) translateY(8px);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
  pointer-events: none;
}

.nav__item:hover .nav__dropdown,
.nav__dropdown.is-open {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
  pointer-events: auto;
}

/* Invisible bridge to prevent gap hover-out */
.nav__dropdown::before {
  content: '';
  position: absolute;
  top: -12px;
  left: 0;
  right: 0;
  height: 12px;
}

.nav__dropdown-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-2);
}

/* Wide dropdown for Solutions (3 columns) */
.nav__dropdown--wide {
  min-width: 720px;
}

.nav__dropdown--wide .nav__dropdown-grid {
  grid-template-columns: 1fr 1fr 1fr;
}

.nav__dropdown-item {
  display: block;
  padding: var(--sp-3) var(--sp-4);
  border-radius: var(--r-md);
  transition: background-color var(--transition-fast);
}

.nav__dropdown-item:hover {
  background-color: var(--c-cream);
}

.nav__dropdown-title {
  font-size: var(--fs-sm);
  font-weight: var(--fw-semibold);
  color: var(--c-ink);
  margin-block-end: var(--sp-1);
}

.nav__dropdown-desc {
  font-size: var(--fs-xs);
  color: var(--c-muted);
  line-height: var(--lh-snug);
}

/* Dropdown section label */
.nav__dropdown-label {
  font-family: var(--f-mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: var(--ls-caps);
  color: var(--c-muted);
  padding: var(--sp-2) var(--sp-4);
  margin-block-end: var(--sp-1);
}

/* ── Nav CTAs ── */
.nav__ctas {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
}

/* ── Mobile hamburger ── */
.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 8px;
  cursor: pointer;
  border-radius: var(--r-md);
}

.nav__toggle:hover {
  background-color: rgba(27, 107, 82, 0.06);
}

.nav__toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--c-ink);
  border-radius: 1px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

/* Hamburger → X animation */
.nav__toggle.is-active .nav__toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav__toggle.is-active .nav__toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav__toggle.is-active .nav__toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ── Mobile overlay ── */
.nav__overlay {
  display: none;
}

/* ── Responsive ── */
@media (max-width: 1024px) {
  .nav__dropdown { min-width: min(520px, 90vw); }
  .nav__dropdown--wide { min-width: min(720px, 90vw); }
}

@media (max-width: 900px) {
  .nav__toggle {
    display: flex;
  }

  .nav,
  .nav__ctas {
    display: none;
  }

  /* Mobile menu open */
  .site-header.nav-open .nav {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    right: 0;
    width: min(380px, 90vw);
    height: 100dvh;
    background-color: var(--c-white);
    padding: 72px var(--sp-5) 0;
    box-shadow: var(--shadow-xl);
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    gap: 0;
    z-index: var(--z-overlay);
    padding-bottom: 140px; /* space for fixed CTA bar */
  }

  .site-header.nav-open .nav__ctas {
    display: flex;
    flex-direction: column;
    position: fixed;
    bottom: 0;
    right: 0;
    width: min(380px, 90vw);
    padding: var(--sp-4) var(--sp-5);
    background-color: var(--c-white);
    border-top: 1px solid var(--c-border);
    z-index: calc(var(--z-overlay) + 1);
    gap: var(--sp-2);
  }

  .site-header.nav-open .nav__ctas .btn {
    width: 100%;
  }

  /* Mobile top-level nav links */
  .site-header.nav-open .nav__link {
    padding: var(--sp-3) var(--sp-2);
    font-size: var(--fs-base);
    border-bottom: 1px solid var(--c-border-subtle);
  }

  /* Mobile dropdown: inline instead of positioned */
  .nav__dropdown,
  .nav__dropdown.is-open,
  .nav__item:hover .nav__dropdown {
    position: static !important;
    transform: none !important;
    min-width: unset !important;
    left: auto !important;
    box-shadow: none;
    border: none;
    padding: var(--sp-2) 0;
    opacity: 1;
    visibility: visible;
    display: none;
    pointer-events: auto;
    background-color: var(--c-cream);
    border-radius: var(--r-md);
    margin: 0;
    width: 100%;
    max-width: 100%;
  }

  .nav__dropdown.is-open {
    display: block !important;
  }

  /* Kill the invisible bridge on mobile */
  .nav__dropdown::before {
    display: none;
  }

  .nav__dropdown-grid {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .nav__dropdown--wide .nav__dropdown-grid {
    grid-template-columns: 1fr;
  }

  /* Compact dropdown items on mobile */
  .nav__dropdown-item {
    padding: var(--sp-2) var(--sp-3);
    border-bottom: 1px solid var(--c-border-subtle);
    overflow: visible;
    text-overflow: unset;
    white-space: normal;
  }

  .nav__dropdown-item:last-child {
    border-bottom: none;
  }

  .nav__dropdown-desc {
    font-size: 11px;
  }

  /* Dropdown section labels on mobile */
  .nav__dropdown-label {
    padding: var(--sp-2) var(--sp-3) 0;
    font-size: 9px;
  }

  /* Overlay backdrop */
  .nav__overlay {
    display: none;
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.4);
    z-index: calc(var(--z-overlay) - 1);
  }

  .site-header.nav-open .nav__overlay {
    display: block;
  }
}

/* ── Skip to content (accessibility) ── */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--sp-4);
  background-color: var(--c-green);
  color: var(--c-white);
  padding: var(--sp-3) var(--sp-6);
  border-radius: var(--r-md);
  font-weight: var(--fw-semibold);
  z-index: var(--z-toast);
  transition: top 0.2s;
}

.skip-link:focus {
  top: var(--sp-4);
}