/* ════════════════════════════════════════════════
   AutoSite Tools — Unified Single Header (GNB)
   ════════════════════════════════════════════════ */

.gnb {
  width: 100%;
  height: 64px;
  position: sticky;
  top: 0;
  z-index: 9999;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  background: rgba(6, 8, 12, 0.9);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  gap: 16px;
}

/* ── Brand Logo ── */
.gnb-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: #ffffff;
  flex-shrink: 0;
}

.gnb-logo-symbol {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.35);
  box-shadow: 0 0 16px rgba(16, 185, 129, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #10b981;
  flex-shrink: 0;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.gnb-brand:hover .gnb-logo-symbol {
  transform: scale(1.06);
  box-shadow: 0 0 22px rgba(16, 185, 129, 0.45);
}

.gnb-logo-row {
  display: flex;
  align-items: center;
  gap: 6px;
}

.gnb-logo-text {
  font-family: 'Montserrat', sans-serif;
  font-size: 19px;
  font-weight: 900;
  letter-spacing: 0.02em;
  line-height: 1;
}

.gnb-logo-text .part-auto {
  background: linear-gradient(135deg, #ffffff 0%, #e0fff0 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.gnb-logo-text .part-site {
  background: linear-gradient(135deg, #10b981 0%, #06b6d4 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.gnb-ko-tag {
  font-family: 'Pretendard', sans-serif;
  font-size: 10.5px;
  font-weight: 800;
  color: #6ee7b7;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.3);
  padding: 2px 7px;
  border-radius: 6px;
  letter-spacing: 0.04em;
}

/* ── Center Menu Links (Unified 6 Tools) ── */
.gnb-links {
  display: flex;
  align-items: center;
  gap: 6px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  padding: 4px 0;
}

.gnb-links::-webkit-scrollbar {
  display: none;
}

.gnb-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 13px;
  border-radius: 9999px;
  font-size: 13px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.72);
  text-decoration: none;
  white-space: nowrap;
  background: transparent;
  border: 1px solid transparent;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  flex-shrink: 0;
}

.gnb-link svg {
  width: 14px;
  height: 14px;
  opacity: 0.85;
  transition: opacity 0.2s;
}

.gnb-link:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.1);
}

.gnb-link:hover svg {
  opacity: 1;
}

.gnb-link.active {
  color: #ffffff;
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.25) 0%, rgba(6, 182, 212, 0.2) 100%);
  border: 1px solid rgba(16, 185, 129, 0.45);
  box-shadow: 0 2px 10px rgba(16, 185, 129, 0.2);
}

.gnb-link.active svg {
  opacity: 1;
  color: #34d399;
}

/* ── Right Utility Action ── */
.gnb-right {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

.gnb-guide-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 13px;
  border-radius: 9999px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: #6ee7b7;
  font-size: 12.5px;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.gnb-guide-btn:hover {
  background: rgba(16, 185, 129, 0.15);
  border-color: rgba(16, 185, 129, 0.4);
  color: #ffffff;
  transform: translateY(-1px);
}

.gnb-guide-btn svg {
  width: 14px;
  height: 14px;
}

/* ── Redundant Second Row Elimination ── */
.tool-nav-bar {
  display: none !important;
}

/* ── Mobile Responsive ── */
@media (max-width: 960px) {
  .gnb {
    padding: 0 16px;
    gap: 10px;
  }
  .gnb-links {
    flex: 1;
    -webkit-overflow-scrolling: touch;
  }
  .gnb-guide-btn span {
    display: none;
  }
  .gnb-guide-btn {
    padding: 7px;
    border-radius: 50%;
  }
}

@media (max-width: 600px) {
  .gnb-brand .gnb-ko-tag {
    display: none;
  }
}