/* ============================================
   GNB (Global Navigation Bar)
   ============================================ */

.gnb {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--gnb-height);
  transition: transform 0.3s var(--ease-out), background 0.3s var(--ease-out), border-color 0.3s var(--ease-out);
}

/* 모바일 hide-on-scroll-down: scrollY > 80px에서 down 스크롤 시 위로 슬라이드아웃,
   up 스크롤 시 다시 등장. 데스크톱은 미적용. */
@media (max-width: 767px) {
  .gnb--hidden {
    transform: translateY(-100%);
  }
}

/* transparent state 상단 dark gradient — 밝은 hero 위에서 메뉴·로고 가독성 보강.
   solid state에선 opacity 0으로 사라짐. */
.gnb::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: calc(var(--gnb-height) + 40px);
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0.45) 0%, rgba(0, 0, 0, 0) 100%);
  pointer-events: none;
  z-index: -1;
  transition: opacity 0.3s var(--ease-out);
}

.gnb--solid::before {
  opacity: 0;
}

.gnb--solid {
  background: var(--overlay-header-scroll);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-light);
}

.gnb__inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-2xl);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.gnb__logo {
  display: inline-flex;
}

.gnb__logo img {
  height: 52px;
  width: auto;
  filter: brightness(0) invert(1); /* transparent GNB: 흰색 (hero 이미지 위) */
  transition: filter 0.3s var(--ease-out);
}

.gnb--solid .gnb__logo img {
  filter: none; /* solid GNB: SVG 원래 burgundy (scroll 후·light section) */
}

/* ── Desktop nav ── */
.gnb__nav {
  flex: 1;
  display: flex;
  justify-content: center;
}

.gnb__menu {
  display: flex;
  gap: var(--space-xl);
}

.gnb__link {
  font-size: 16px;
  font-weight: 500;
  color: var(--color-text-invert);
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 8px 0;
  transition: color 0.2s;
}

.gnb--solid .gnb__link {
  color: var(--color-text);
}

.gnb__chevron {
  font-size: 12px;
  transition: transform 0.2s;
}

/* ── Dropdown ── */
.gnb__dropdown {
  position: absolute;
  top: calc(var(--gnb-height) - 8px);
  left: 50%;
  transform: translateX(-50%);
  min-width: 320px;
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: 8px;
  box-shadow: var(--shadow-lg);
  padding: var(--space-md);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s, visibility 0.2s;
}

/* Invisible hover bridge — keeps hover state alive while the cursor crosses
   the visual gap between the trigger button and the dropdown panel. */
.gnb__dropdown::before {
  content: '';
  position: absolute;
  top: -16px;
  left: 0;
  right: 0;
  height: 16px;
}

.gnb__dropdown.is-open {
  opacity: 1;
  visibility: visible;
}

.gnb__item {
  position: relative;
}

.gnb__dropdown-item {
  display: flex;
  gap: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  border-radius: 6px;
  color: var(--color-text);
  transition: background 0.15s;
}

.gnb__dropdown-item:hover {
  background: var(--color-bg-surface);
}

.gnb__dropdown-item strong {
  display: block;
  font-size: 16px;
  font-weight: 600;
}

.gnb__dropdown-item span {
  font-size: 15px;
  color: var(--color-text-sub);
}

.gnb__dropdown-icon {
  width: 20px;
  height: 20px;
  margin-top: 2px;
  flex-shrink: 0;
  color: var(--color-primary);
}

/* ── Right actions ── */
.gnb__actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.gnb__lang {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text-invert);
  display: flex;
  align-items: center;
  gap: 4px;
}

.gnb--solid .gnb__lang {
  color: var(--color-text);
}

.gnb__lang-wrapper {
  position: relative;
}

.gnb__lang-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: 8px;
  box-shadow: var(--shadow-lg);
  padding: 4px;
  min-width: 80px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s, visibility 0.2s;
}

.gnb__lang-menu.is-open {
  opacity: 1;
  visibility: visible;
}

.gnb__lang-option {
  display: block;
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text);
  border-radius: 6px;
  text-align: center;
  transition: background 0.15s;
}

.gnb__lang-option:hover {
  background: var(--color-bg-surface);
}

.gnb__cta {
  font-size: 15px;
  padding: 10px 20px;
}

/* ── Hamburger ── */
.gnb__hamburger {
  display: none;
  width: 24px;
  height: 24px;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
}

.gnb__hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text-invert);
  transition: background 0.2s;
}

.gnb--solid .gnb__hamburger span {
  background: var(--color-text);
}

/* ── Mobile panel ── */
.gnb__mobile-panel {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  background: var(--color-bg);
  z-index: 200;
  transform: translateX(-100%);
  transition: transform 0.3s var(--ease-out);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.gnb__mobile-panel.is-open {
  transform: translateX(0);
}

.gnb__mobile-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--color-border-light);
}

.gnb__mobile-close {
  font-size: 30px;
  color: var(--color-text);
}

.gnb__mobile-nav {
  flex: 1;
  padding: var(--space-md) var(--space-lg);
}

.gnb__mobile-parent {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: var(--space-md) 0;
  font-size: 20px;
  font-weight: 600;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border-light);
}

.gnb__mobile-link {
  display: block;
  padding: var(--space-md) 0;
  font-size: 20px;
  font-weight: 600;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border-light);
}

.gnb__mobile-sub {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s var(--ease-out);
}

.gnb__mobile-sub.is-open {
  max-height: 400px;
}

.gnb__mobile-sub li a {
  display: block;
  padding: var(--space-sm) var(--space-lg);
  font-size: 17px;
  color: var(--color-text-sub);
}

.gnb__mobile-footer {
  padding: var(--space-lg);
  border-top: 1px solid var(--color-border-light);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.gnb__mobile-footer .gnb__lang {
  color: var(--color-text);
}

.gnb__mobile-footer .gnb__lang-menu {
  top: auto;
  bottom: calc(100% + 8px);
}

/* ── Responsive ── */
@media (max-width: 1023px) {
  .gnb__nav,
  .gnb__actions {
    display: none;
  }
  .gnb__hamburger {
    display: flex;
  }
  .gnb {
    height: var(--gnb-height-mobile);
  }
  .gnb__inner {
    padding: 0 var(--space-lg);
  }
}

@media (min-width: 1024px) {
  .gnb__mobile-panel {
    display: none;
  }
}