/**
 * ToolFlux Lab - Header, Navigation, Footer & Structural Layout
 */

/* =========================================================
   HEADER
========================================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-color);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  gap: var(--space-4);
}

/* Brand Logo */
.brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  text-decoration: none;
  font-weight: 800;
  font-size: var(--text-lg);
  color: var(--text-main);
  letter-spacing: -0.03em;
}

.brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: var(--primary);
  color: #FFFFFF;
  border-radius: var(--radius-sm);
  font-weight: 800;
  font-size: var(--text-sm);
  letter-spacing: -0.05em;
  box-shadow: var(--shadow-sm);
}

.brand-name {
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.brand-tag {
  font-size: var(--text-xs);
  color: var(--primary);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Header Nav */
.header-nav {
  display: none;
  align-items: center;
  gap: var(--space-6);
}

@media (min-width: 1024px) {
  .header-nav {
    display: flex;
  }
}

.nav-link {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-muted);
  transition: color var(--transition-fast);
  padding: var(--space-2) var(--space-1);
}

.nav-link:hover,
.nav-link.active {
  color: var(--text-main);
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* Quick Search Button in Header */
.header-search-btn {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--bg-surface-secondary);
  border: 1px solid var(--border-color);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  color: var(--text-muted);
  font-size: var(--text-xs);
  font-weight: 500;
  transition: all var(--transition-fast);
}

.header-search-btn:hover {
  border-color: var(--primary);
  color: var(--text-main);
  background: var(--bg-surface);
}

@media (max-width: 640px) {
  .header-search-btn span,
  .header-search-btn .kbd-badge {
    display: none;
  }
  .header-search-btn {
    padding: 0;
    width: 36px;
    height: 36px;
    justify-content: center;
  }
  .header-actions {
    gap: 6px;
  }
}

.kbd-badge {
  display: inline-flex;
  align-items: center;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  padding: 1px 5px;
  border-radius: var(--radius-xs);
  font-family: inherit;
  font-size: 10px;
  font-weight: 600;
  color: var(--text-muted);
}

/* Icon Buttons (Theme, Lang, Mobile Menu) */
.btn-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-surface);
  color: var(--text-muted);
  transition: all var(--transition-fast);
}

.btn-icon:hover {
  background: var(--bg-surface-secondary);
  color: var(--text-main);
  border-color: var(--border-color);
}

.lang-toggle {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: var(--space-1) var(--space-2);
  height: 36px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-surface);
  color: var(--text-main);
  font-size: var(--text-xs);
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.lang-toggle:hover {
  background: var(--bg-surface-secondary);
}

.menu-toggle {
  display: inline-flex;
}

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

/* Mobile Drawer Navigation */
.mobile-nav-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.mobile-nav-backdrop.open {
  opacity: 1;
  pointer-events: auto;
}

.mobile-nav-drawer {
  position: fixed;
  top: 0;
  bottom: 0;
  inset-inline-end: 0;
  width: 85%;
  max-width: 320px;
  background: var(--bg-surface);
  border-inline-start: 1px solid var(--border-color);
  z-index: 1001;
  padding: var(--space-6);
  display: none;
  flex-direction: column;
  gap: var(--space-6);
  transform: translateX(100%);
  transition: transform var(--transition-normal);
  pointer-events: none;
  box-sizing: border-box;
}

html[dir="rtl"] .mobile-nav-drawer {
  transform: translateX(-100%);
}

.mobile-nav-drawer.open {
  display: flex;
  transform: translateX(0);
  pointer-events: auto;
}

.mobile-nav-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: var(--space-4);
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-base);
  font-weight: 500;
  padding: var(--space-2) 0;
  color: var(--text-main);
}

/* =========================================================
   SECTIONS & SPACING
========================================================= */
.site-section {
  padding-block: var(--space-12);
}

@media (min-width: 768px) {
  .site-section {
    padding-block: var(--space-16);
  }
}

.section-header {
  margin-bottom: var(--space-8);
  max-width: 680px;
}

.section-title {
  font-size: var(--text-2xl);
  margin-bottom: var(--space-2);
}

@media (min-width: 768px) {
  .section-title {
    font-size: var(--text-3xl);
  }
}

.section-desc {
  font-size: var(--text-base);
  color: var(--text-muted);
}

/* =========================================================
   FOOTER
========================================================= */
.site-footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-color);
  padding-top: var(--space-12);
  padding-bottom: var(--space-8);
  margin-top: var(--space-16);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
}

@media (min-width: 640px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .footer-grid {
    grid-template-columns: 2fr repeat(3, 1fr);
    gap: var(--space-10);
  }
}

.footer-col-title {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--text-main);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-4);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-link {
  font-size: var(--text-sm);
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--primary);
}

.footer-bottom {
  margin-top: var(--space-10);
  padding-top: var(--space-6);
  border-top: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  font-size: var(--text-xs);
  color: var(--text-muted);
}

@media (min-width: 768px) {
  .footer-bottom {
    flex-direction: row;
  }
}

/* =========================================================
   AD PLACEHOLDER (AdSense Compliant & Non-Intrusive)
========================================================= */
.ad-slot-container {
  margin-block: var(--space-8);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.ad-wrapper {
  width: 100%;
  max-width: 728px;
  min-height: 90px;
  background: var(--bg-surface-secondary);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.ad-label {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 4px;
}