/* ============================================
   LAYOUT.CSS — Header, Nav, Hero, Grid, Footer
   ============================================ */

/* ---------- Progress Bar ---------- */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: var(--progress-height);
  background: linear-gradient(90deg, var(--color-accent), var(--color-accent-light));
  z-index: calc(var(--z-sticky) + 1);
  transition: width 100ms linear;
  will-change: width;
}

/* ---------- Header ---------- */
.header {
  position: sticky;
  top: var(--progress-height);
  z-index: var(--z-sticky);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: rgba(255, 255, 255, 0.92);
}

[data-theme="dark"] .header {
  background: rgba(26, 29, 39, 0.92);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .header {
    background: rgba(26, 29, 39, 0.92);
  }
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  gap: var(--space-3);
}

/* ---------- Logo ---------- */
.logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  flex-shrink: 0;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-dark));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: var(--font-bold);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-title {
  font-family: var(--font-heading);
  font-weight: var(--font-bold);
  font-size: var(--text-sm);
  color: var(--color-text);
  line-height: 1.2;
}

.logo-subtitle {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  line-height: 1.2;
}

/* ---------- Desktop Nav ---------- */
.nav-desktop {
  display: none;
  align-items: center;
  gap: var(--space-1);
}

@media (min-width: 960px) {
  .nav-desktop {
    display: flex;
  }
}

.nav-link {
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--color-text-secondary);
  border-radius: var(--radius-md);
  transition: color var(--transition-fast), background var(--transition-fast);
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-accent);
  background: var(--color-surface-alt);
}

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

.btn-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  background: transparent;
  color: var(--color-text-secondary);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: color var(--transition-fast), background var(--transition-fast);
  position: relative;
}

.btn-icon:hover {
  color: var(--color-accent);
  background: var(--color-surface-alt);
}

/* ---------- Search Overlay ---------- */
.search-overlay {
  display: none;
  position: fixed;
  inset: 0;
  z-index: var(--z-overlay);
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  padding: var(--space-4);
  padding-top: calc(var(--header-height) + var(--progress-height) + var(--space-4));
}

.search-overlay.active {
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

.search-box {
  width: 100%;
  max-width: 600px;
  background: var(--color-surface);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
}

.search-input-wrap {
  display: flex;
  align-items: center;
  padding: var(--space-4);
  gap: var(--space-3);
  border-bottom: 1px solid var(--color-border);
}

.search-input-wrap .icon {
  color: var(--color-text-muted);
  font-size: var(--text-xl);
  flex-shrink: 0;
}

.search-input {
  flex: 1;
  border: none;
  outline: none;
  background: transparent;
  font-size: var(--text-base);
  color: var(--color-text);
}

.search-input::placeholder {
  color: var(--color-text-muted);
}

.search-results {
  max-height: 400px;
  overflow-y: auto;
}

.search-result-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  cursor: pointer;
  transition: background var(--transition-fast);
  border-bottom: 1px solid var(--color-border-light);
  text-decoration: none;
  color: var(--color-text);
}

.search-result-item:hover,
.search-result-item.focused {
  background: var(--color-surface-alt);
}

.search-result-section {
  font-size: var(--text-xs);
  color: var(--color-accent);
  font-weight: var(--font-semibold);
}

.search-result-text {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.search-empty {
  padding: var(--space-8);
  text-align: center;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

.search-shortcut {
  display: none;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-2);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
}

@media (min-width: 960px) {
  .search-shortcut {
    display: flex;
  }
}

/* ---------- Mobile Nav Drawer ---------- */
.mobile-nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  z-index: var(--z-overlay);
  background: rgba(0, 0, 0, 0.5);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.mobile-nav-overlay.active {
  display: block;
  opacity: 1;
}

.mobile-nav {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: 280px;
  max-width: 85vw;
  z-index: var(--z-modal);
  background: var(--color-surface);
  transform: translateX(-100%);
  transition: transform var(--transition-base);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.mobile-nav.active {
  transform: translateX(0);
}

.mobile-nav-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--color-border);
}

.mobile-nav-links {
  flex: 1;
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--color-text-secondary);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  text-decoration: none;
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
  background: var(--color-surface-alt);
  color: var(--color-accent);
}

.mobile-nav-link .nav-number {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface-alt);
  color: var(--color-accent);
  font-family: var(--font-heading);
  font-weight: var(--font-bold);
  font-size: var(--text-xs);
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.mobile-nav-link.active .nav-number {
  background: var(--color-accent);
  color: #fff;
}

.mobile-nav-footer {
  padding: var(--space-4) var(--space-5);
  border-top: 1px solid var(--color-border);
}

.nav-toggle {
  display: flex;
}

@media (min-width: 960px) {
  .nav-toggle {
    display: none;
  }
}

/* ---------- Hero ---------- */
.hero {
  background: linear-gradient(135deg, #1a1d2e 0%, #2a2d3e 50%, #1a1d2e 100%);
  color: #fff;
  padding: var(--space-10) 0;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 80%;
  height: 200%;
  background: radial-gradient(circle, rgba(201, 168, 76, 0.08) 0%, transparent 60%);
  pointer-events: none;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(201, 168, 76, 0.15);
  border: 1px solid rgba(201, 168, 76, 0.3);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: var(--font-semibold);
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-6);
}

.hero h1 {
  color: #fff;
  margin-bottom: var(--space-3);
  font-size: var(--text-2xl);
}

@media (min-width: 640px) {
  .hero h1 {
    font-size: var(--text-4xl);
  }
}

.hero-subtitle {
  font-size: var(--text-lg);
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: var(--space-8);
}

/* ---------- Contact Bar ---------- */
.contact-bar {
  background: var(--color-primary);
  padding: var(--space-4) 0;
}

[data-theme="dark"] .contact-bar {
  background: var(--color-surface-alt);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .contact-bar {
    background: var(--color-surface-alt);
  }
}

.contact-bar-inner {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  align-items: center;
  text-align: center;
}

@media (min-width: 640px) {
  .contact-bar-inner {
    flex-direction: row;
    justify-content: center;
    gap: var(--space-8);
  }
}

.contact-bar-title {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--text-sm);
}

.contact-item .icon {
  color: var(--color-accent);
}

/* ---------- Main ---------- */
.main {
  min-height: 60vh;
}

/* ---------- Back to Top ---------- */
.back-to-top {
  position: fixed;
  bottom: var(--space-6);
  right: var(--space-6);
  z-index: var(--z-dropdown);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent);
  color: #fff;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--transition-base), visibility var(--transition-base), transform var(--transition-base);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--color-accent-light);
  transform: translateY(-2px);
}

/* ---------- TOC Button (Mobile) ---------- */
.toc-toggle {
  position: fixed;
  bottom: var(--space-6);
  left: var(--space-6);
  z-index: var(--z-dropdown);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  color: var(--color-accent);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  cursor: pointer;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--transition-base), visibility var(--transition-base), transform var(--transition-base);
}

.toc-toggle.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

@media (min-width: 960px) {
  .toc-toggle {
    display: none;
  }
}

/* ---------- Footer ---------- */
.footer {
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.7);
  padding: var(--space-8) 0;
  text-align: center;
}

[data-theme="dark"] .footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .footer {
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
  }
}

.footer-title {
  font-family: var(--font-heading);
  font-weight: var(--font-bold);
  color: var(--color-accent);
  margin-bottom: var(--space-2);
}

.footer p {
  font-size: var(--text-sm);
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: var(--space-1);
}

[data-theme="dark"] .footer p {
  color: var(--color-text-muted);
}

.footer a {
  color: var(--color-accent);
}

/* ---------- Print Header ---------- */
.print-header {
  display: none;
}

@media print {
  .print-header {
    display: block;
    text-align: center;
    padding: 1rem 0;
    border-bottom: 2px solid #000;
    margin-bottom: 1rem;
  }
  .print-header h1 {
    font-size: 18pt;
    color: #000;
  }
  .print-header p {
    color: #333;
    font-size: 11pt;
  }
}