/* ============================================
   HEADER NAV — Horizontal navbar with hover dropdowns
   ============================================ */

.header-nav {
  position: fixed;
  top: 16px;
  left: 50%;
  transform: translateX(-50%);
  width: calc(100% - 32px);
  max-width: 1200px;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 16px;
  transition: background 400ms cubic-bezier(0.22, 1, 0.36, 1), border-color 400ms cubic-bezier(0.22, 1, 0.36, 1), transform 500ms cubic-bezier(0.22, 1, 0.36, 1);
}

.header-nav.is-hidden {
  transform: translateX(-50%) translateY(calc(-100% - 24px));
}

/* Scrolled past hero — white bg, dark text */
.header-nav.is-scrolled {
  background: rgba(255, 255, 255, 0.85);
  border-color: rgba(0, 0, 0, 0.08);
}

.header-nav.is-scrolled .header-nav__item-btn {
  color: var(--color-text);
}

.header-nav.is-scrolled .header-nav__item-btn:hover {
  background: var(--color-surface);
}

.header-nav.is-scrolled .header-nav__sign-in {
  color: var(--color-text);
}

.header-nav.is-scrolled .header-nav__sign-in:hover {
  background: var(--color-surface);
}

.header-nav.is-scrolled .header-nav__cta {
  background: var(--color-text);
  color: var(--color-text-inverse);
}

.header-nav.is-scrolled .header-nav__toggle span {
  background: var(--color-text);
}

.header-nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-xl);
  height: var(--navbar-height);
}

/* --- Logo --- */
.header-nav__logo {
  flex-shrink: 0;
}

.header-nav__logo img {
  height: 40px;
  display: block;
  filter: brightness(0) invert(1);
  transition: filter 400ms cubic-bezier(0.22, 1, 0.36, 1);
}

.header-nav.is-scrolled .header-nav__logo img {
  filter: none;
}

/* --- Nav links (center-left) --- */
.header-nav__links {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  margin-left: var(--spacing-2xl);
}

.header-nav__item {
  position: relative;
}

.header-nav__item-btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 8px 14px;
  border: none;
  background: none;
  font-family: var(--font-family-body);
  font-size: 0.9375rem;
  font-weight: 500;
  color: #FFFFFF;
  cursor: pointer;
  border-radius: var(--radius-md);
  transition: background var(--transition-fast), color var(--transition-fast);
  text-decoration: none;
}

.header-nav__item-btn:hover {
  background: rgba(255, 255, 255, 0.1);
}

.header-nav__chevron {
  width: 14px;
  height: 14px;
  transition: transform 200ms ease;
}

.header-nav__item:hover .header-nav__chevron {
  transform: rotate(180deg);
}

/* --- Dropdown panel --- */
.header-nav__dropdown {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  width: 560px;
  background: #FFFFFF;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
  padding: var(--spacing-md);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 200ms ease, transform 200ms ease, visibility 200ms ease;
  /* Grid layout: text left, image right */
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  align-items: center;
}

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

/* Bridge element to prevent gap between button and dropdown */
.header-nav__dropdown::before {
  content: '';
  position: absolute;
  top: -12px;
  left: 0;
  right: 0;
  height: 12px;
}

.header-nav__dropdown-text {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.header-nav__dropdown-img {
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--color-surface);
}

.header-nav__dropdown-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.header-nav__dropdown-title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
}

.header-nav__dropdown-desc {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  line-height: 1.5;
}

/* --- Right actions --- */
.header-nav__actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-left: auto;
}

.header-nav__sign-in {
  font-size: 0.9375rem;
  font-weight: 500;
  color: #FFFFFF;
  text-decoration: none;
  padding: 8px 14px;
  border-radius: var(--radius-md);
  transition: background var(--transition-fast);
}

.header-nav__sign-in:hover {
  background: rgba(255, 255, 255, 0.1);
}

.header-nav__cta {
  display: inline-flex;
  align-items: center;
  padding: 10px 20px;
  background: #FFFFFF;
  color: #0F172A;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: opacity var(--transition-fast);
}

.header-nav__cta:hover {
  opacity: 0.85;
}

/* --- Mobile toggle --- */
.header-nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  padding: 8px;
  border: none;
  background: none;
  cursor: pointer;
}

.header-nav__toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: #FFFFFF;
  border-radius: 2px;
  transition: transform 200ms ease, opacity 200ms ease;
}

/* --- Mobile (<=768px) --- */
@media (max-width: 768px) {
  .header-nav {
    top: 8px;
    width: calc(100% - 16px);
    border-radius: 12px;
  }

  .header-nav__inner {
    padding: 0 var(--spacing-sm);
    height: 56px;
  }

  .header-nav__links {
    display: none;
    position: absolute;
    top: var(--navbar-height);
    left: 0;
    right: 0;
    flex-direction: column;
    background: #FFFFFF;
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-md);
    gap: 0;
    margin-left: 0;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
  }

  .header-nav__links.is-open {
    display: flex;
  }

  .header-nav__toggle {
    display: flex;
  }

  /* Hide dropdowns on mobile */
  .header-nav__dropdown {
    display: none;
  }

  .header-nav__item-btn {
    width: 100%;
    justify-content: space-between;
    padding: 12px 14px;
    color: #111827;
  }

  .header-nav__sign-in {
    display: none;
  }

  .header-nav__actions {
    gap: var(--spacing-sm);
  }

  .header-nav__cta {
    padding: 8px 14px;
    font-size: 0.8125rem;
  }
}

/* --- Tablet (769px-1024px) --- */
@media (min-width: 769px) and (max-width: 1024px) {
  .header-nav__inner {
    padding: 0 var(--spacing-lg);
  }

  .header-nav__links {
    gap: 0;
    margin-left: var(--spacing-lg);
  }

  .header-nav__item-btn {
    padding: 8px 10px;
    font-size: 0.875rem;
  }

  .header-nav__dropdown {
    width: 440px;
  }

  .header-nav__sign-in {
    padding: 8px 10px;
    font-size: 0.875rem;
  }

  .header-nav__cta {
    padding: 8px 16px;
    font-size: 0.875rem;
  }
}

/* --- Small phone (<=390px) --- */
@media (max-width: 390px) {
  .header-nav__logo img {
    height: 22px;
  }

  .header-nav__cta {
    padding: 6px 12px;
    font-size: 0.75rem;
  }
}