/* ═══════════════════════════════════════════════════════════
   灵犀漆语 · 布局系统
   Header, Sidebar, Content, Mobile Nav, Responsive Grid
   ═══════════════════════════════════════════════════════════ */

/* ── Top Navigation ── */
.top-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: rgba(8, 8, 13, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-divider);
  z-index: var(--z-sticky);
  display: flex;
  align-items: center;
  padding: 0 var(--space-6);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-serif);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text-primary);
  text-decoration: none;
  white-space: nowrap;
}

.nav-brand .brand-icon {
  font-size: 1.5rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.nav-brand .brand-icon svg {
  width: 24px;
  height: 24px;
}

.nav-brand .brand-sub {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  font-family: var(--font-sans);
  font-weight: 400;
}

.nav-spacer { flex: 1; }

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  cursor: pointer;
  text-decoration: none;
}
.nav-link svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.nav-link:hover { color: var(--color-text-primary); background: var(--color-bg-hover); }
.nav-link.active { color: var(--color-gold); background: var(--color-gold-glow); }

.nav-user {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background var(--transition-fast);
}

.nav-user:hover { background: var(--color-bg-hover); }

.nav-avatar {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-full);
  background: var(--gradient-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-text-inverse);
}

.nav-user-info {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.nav-user-name { 
  font-size: var(--text-sm); 
  font-weight: 500; 
  line-height: 1.2; 
}

.nav-user-role { 
  font-size: var(--text-xs); 
  color: var(--color-text-muted); 
  line-height: 1.2;
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
}

/* ── Sidebar ── */
.app-layout {
  display: flex;
  min-height: 100vh;
  padding-top: var(--header-height);
}

.sidebar {
  position: fixed;
  top: var(--header-height);
  left: 0;
  bottom: 0;
  width: var(--sidebar-width);
  background: var(--color-bg-secondary);
  border-right: 1px solid var(--color-divider);
  overflow-y: auto;
  padding: var(--space-4);
  z-index: var(--z-dropdown);
  transition: transform var(--transition-base);
}

.sidebar-section {
  margin-bottom: var(--space-6);
}

.sidebar-title {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: var(--space-2) var(--space-4);
  margin-bottom: var(--space-2);
}

.sidebar-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  cursor: pointer;
  text-decoration: none;
}

.sidebar-item:hover { color: var(--color-text-primary); background: var(--color-bg-hover); }
.sidebar-item.active {
  color: var(--color-gold);
  background: var(--color-gold-glow);
  font-weight: 500;
}

.sidebar-item .item-icon { font-size: var(--text-lg); width: 24px; text-align: center; }
.sidebar-item .item-badge {
  margin-left: auto;
  font-size: var(--text-xs);
  background: var(--color-vermillion-glow);
  color: var(--color-vermillion-light);
  padding: 1px 6px;
  border-radius: var(--radius-full);
}

/* ── Main Content ── */
.main-content {
  flex: 1;
  min-width: 0;
  margin-left: var(--sidebar-width);
  padding: var(--space-8);
  min-height: calc(100vh - var(--header-height));
}

.page-header {
  margin-bottom: var(--space-8);
  animation: fadeIn 0.4s ease;
}

.page-title {
  font-size: var(--text-3xl);
  font-weight: 700;
  margin-bottom: var(--space-2);
}

.page-subtitle {
  font-size: var(--text-base);
  color: var(--color-text-muted);
}

/* ── Content Grid ── */
.grid {
  display: grid;
  gap: var(--space-6);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* ── Full-page layout (no sidebar) ── */
.page-full {
  width: 100%;
  min-height: 100vh;
}

.page-centered {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: var(--space-8);
}

/* ── Auth Page Layout ── */
.auth-container {
  width: 100%;
  max-width: 440px;
  animation: slideUp 0.6s ease;
}

.auth-card {
  background: var(--gradient-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-10);
  backdrop-filter: blur(12px);
}

.auth-header {
  text-align: center;
  margin-bottom: var(--space-8);
}

.auth-logo {
  font-size: 2.5rem;
  margin-bottom: var(--space-4);
}

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

.auth-subtitle {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* ── Mobile Bottom Nav ── */
.mobile-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: var(--mobile-nav-height);
  background: rgba(8, 8, 13, 0.95);
  backdrop-filter: blur(20px);
  border-top: 1px solid var(--color-divider);
  z-index: var(--z-sticky);
  padding: 0 var(--space-2);
}

.mobile-nav-items {
  display: flex;
  align-items: center;
  justify-content: space-around;
  height: 100%;
}

.mobile-nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: var(--space-2);
  color: var(--color-text-muted);
  font-size: 10px;
  text-decoration: none;
  transition: color var(--transition-fast);
  cursor: pointer;
  min-width: 56px;
  position: relative;
}

.mobile-nav-item .nav-icon { 
  font-size: 20px; 
  transition: transform var(--transition-fast); 
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 2px; /* 图标与文字之间的小间距 */
}
.mobile-nav-item .nav-icon svg {
  width: 22px;
  height: 22px;
  stroke-width: 1.5; /* 更细的线条 */
}
.mobile-nav-item:hover { color: var(--color-text-primary); }

/* Active state for mobile nav */
.mobile-nav-item.active { 
  color: var(--color-gold); 
  font-weight: 600; 
}
.mobile-nav-item.active .nav-icon { 
  transform: scale(1.15); /* 稍微减小缩放，更精致 */
  filter: drop-shadow(0 0 6px rgba(212,175,55,0.5)); /* 减弱发光效果 */
}
.mobile-nav-item.active .nav-icon svg {
  stroke-width: 1.8; /* 激活时稍微加粗 */
}
.mobile-nav-item.active::after {
  content: '';
  position: absolute;
  top: -2px;
  width: 24px;
  height: 2px;
  background: var(--color-gold);
  border-radius: 0 0 2px 2px;
  box-shadow: 0 0 8px var(--color-gold);
}

/* ── Mobile hamburger ── */
.hamburger {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  background: none;
  border: none;
  color: var(--color-text-primary);
  font-size: 1.4rem;
  cursor: pointer;
}

/* ── Responsive ── */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .hamburger { display: flex; }

  .sidebar {
    transform: translateX(-100%);
    width: 280px;
  }
  .sidebar.open { transform: translateX(0); }

  .main-content {
    margin-left: 0;
    padding: var(--space-4);
    padding-bottom: calc(var(--mobile-nav-height) + var(--space-4));
  }

  .mobile-nav { display: block; }

  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }

  .page-header .page-title { font-size: var(--text-2xl); }

  .top-nav { padding: 0 var(--space-4); }

  .nav-links { display: none; }

  .nav-user-info { display: none; }

  .auth-card { padding: var(--space-6); }

  .modal { max-width: calc(100vw - 32px); }

  /* Hide desktop nav items on mobile */
  .desktop-only { display: none !important; }
}

@media (max-width: 480px) {
  html { font-size: 14px; }
  
  .page-centered { padding: var(--space-4); }
  .auth-container { max-width: 100%; }
}

/* ── Overlay for mobile sidebar ── */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: calc(var(--z-dropdown) - 1);
}

.sidebar-overlay.active { display: block; }

/* ── Flex utilities ── */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }

/* ── Text utilities ── */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-muted { color: var(--color-text-muted); }
.text-gold { color: var(--color-gold); }
.text-sm { font-size: var(--text-sm); }
.text-xs { font-size: var(--text-xs); }
.font-serif { font-family: var(--font-serif); }
.font-bold { font-weight: 700; }

/* ── Spacing utilities ── */
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.p-4 { padding: var(--space-4); }
.p-6 { padding: var(--space-6); }

.w-full { width: 100%; }