#app-container {
  display: grid;
  grid-template-columns: 260px 1fr;
  grid-template-rows: 70px 1fr;
  grid-template-areas:
    "sidebar topbar"
    "sidebar main";
  height: 100vh;
  width: 100%;
  max-width: 100%;
  overflow: hidden;
}

/* Sidebar Styling */
#sidebar {
  grid-area: sidebar;
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  height: 100%;
  overflow-y: auto;
  z-index: 100;
}

.brand-section {
  padding: 20px 24px;
  display: flex;
  align-items: center;
  gap: 12px;
  border-bottom: 1px solid var(--border-color);
}

.brand-logo {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--info));
  border-radius: var(--border-radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 800;
  font-size: 1.2rem;
  box-shadow: var(--shadow-glow);
}

.brand-name {
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.5px;
}

.brand-subtitle {
  font-size: 0.7rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-top: 2px;
}

.sidebar-menu {
  list-style: none;
  padding: 16px 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  flex-grow: 1;
}

.menu-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
  border-radius: var(--border-radius-md);
  transition: all var(--transition-fast);
  cursor: pointer;
}

.menu-item:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.menu-item.active {
  background-color: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

[data-theme="dark"] .menu-item.active {
  background-color: var(--primary-glow);
  color: var(--primary-hover);
}

.menu-item svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.sidebar-footer {
  padding: 16px;
  border-top: 1px solid var(--border-color);
  font-size: 0.75rem;
  color: var(--text-muted);
  text-align: center;
}

/* Topbar Styling */
#topbar {
  grid-area: topbar;
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  z-index: 90;
}

.topbar-left {
  display: flex;
  align-items: center;
  gap: 16px;
}

.breadcrumb-title {
  font-size: 1.25rem;
  font-weight: 700;
}

.topbar-right {
  display: flex;
  align-items: center;
  gap: 20px;
  min-width: 0;
  flex: 1;
  justify-content: flex-end;
}

.system-time {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-family: var(--font-mono);
}

/* Hamburger Button Toggle */
.hamburger-btn {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-md);
  width: 44px; /* Touch target-friendly */
  height: 44px;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-right: 12px;
}

.hamburger-btn:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.hamburger-btn svg {
  width: 24px;
  height: 24px;
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.theme-toggle, .notification-bell {
  background: none;
  border: 1px solid var(--border-color);
  border-radius: 50%;
  width: 38px;
  height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  cursor: pointer;
  position: relative;
  transition: all var(--transition-fast);
}

.theme-toggle:hover, .notification-bell:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--text-muted);
}

.notification-badge {
  position: absolute;
  top: 0;
  right: 0;
  background-color: var(--danger);
  color: white;
  font-size: 0.7rem;
  font-weight: 700;
  border-radius: 50%;
  width: 16px;
  height: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--bg-secondary);
}

.user-selector-container {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  flex: 1 1 auto;
}

.user-select {
  padding: 6px 12px;
  border-radius: var(--border-radius-md);
  border: 1px solid var(--border-color);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  outline: none;
  max-width: 100%;
  width: 100%;
  min-width: 0;
  text-overflow: ellipsis;
  white-space: nowrap;
  overflow: hidden;
  flex-shrink: 1;
}

.user-select:focus {
  border-color: var(--border-focus);
}

/* Main Content Area */
#main-viewport {
  grid-area: main;
  overflow-y: auto;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 24px;
  position: relative;
}

/* Grid & Cards System */
.grid-cols-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.grid-cols-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.grid-cols-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.grid-cols-1-2 {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 20px;
}

.grid-cols-2-1 {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 20px;
}

.stat-card {
  padding: 20px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 110px;
  position: relative;
  overflow: hidden;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.stat-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.stat-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
}

.stat-icon {
  width: 32px;
  height: 32px;
  border-radius: var(--border-radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
}

.stat-value {
  font-size: 1.75rem;
  font-weight: 700;
  margin-top: 8px;
  font-family: var(--font-title);
}

.stat-footer {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 6px;
  display: flex;
  align-items: center;
  gap: 4px;
}

.stat-trend-up {
  color: var(--success);
  font-weight: 600;
}

.stat-trend-down {
  color: var(--danger);
  font-weight: 600;
}

/* Page Header */
.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.page-header-actions {
  display: flex;
  gap: 12px;
}

/* Button UI */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.9rem;
  border-radius: var(--border-radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
  min-height: 44px; /* Ensure 44px touch targets */
}

.btn-primary {
  background-color: var(--primary);
  color: var(--text-on-accent);
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  box-shadow: var(--shadow-glow);
}

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

.btn-secondary:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.btn-danger {
  background-color: var(--danger);
  color: var(--text-on-accent);
}

.btn-danger:hover {
  background-color: var(--danger-hover);
}

.btn-success {
  background-color: var(--success);
  color: var(--text-on-accent);
}

.btn-success:hover {
  background-color: var(--success-hover);
}

.btn-sm {
  padding: 6px 12px;
  font-size: 0.8rem;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* Table Design */
.table-container {
  overflow-x: auto;
  width: 100%;
  -webkit-overflow-scrolling: touch; /* Smooth iOS swipe scrolling */
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.875rem;
}

.data-table th {
  background-color: var(--bg-tertiary);
  color: var(--text-secondary);
  padding: 12px 16px;
  font-weight: 600;
  border-bottom: 1px solid var(--border-color);
  user-select: none;
}

.data-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-primary);
}

.data-table tbody tr {
  transition: background-color var(--transition-fast);
}

.data-table tbody tr:hover {
  background-color: var(--bg-tertiary);
}

/* Badge Tags */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 8px;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge-success {
  background-color: var(--success-light);
  color: var(--success-hover);
}

.badge-warning {
  background-color: var(--warning-light);
  color: var(--warning-hover);
}

.badge-danger {
  background-color: var(--danger-light);
  color: var(--danger-hover);
}

.badge-info {
  background-color: var(--info-light);
  color: var(--info-hover);
}

/* Form Styles */
.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 16px;
}

.form-group label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.form-control, select, textarea {
  padding: 10px 14px;
  border-radius: var(--border-radius-md);
  border: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.9rem;
  outline: none;
  transition: border-color var(--transition-fast);
  width: 100%;
  min-height: 44px; /* Ensure 44px touch targets */
}

.form-control:focus, select:focus, textarea:focus {
  border-color: var(--border-focus);
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 16px;
}

/* Search bar and Filters */
.filters-bar {
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
  padding: 16px;
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  border-radius: var(--border-radius-md) var(--border-radius-md) 0 0;
}

.search-input-wrapper {
  position: relative;
  flex-grow: 1;
  min-width: 200px;
}

.search-input-wrapper svg {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  width: 16px;
  height: 16px;
}

.search-input-wrapper input {
  padding-left: 36px;
}

/* Modals */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: rgba(0, 0, 0, 0.4);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.modal-container {
  width: 90%;
  max-width: 650px;
  max-height: 90vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  transform: translateY(20px);
  transition: transform var(--transition-normal);
}

.modal-overlay.active .modal-container {
  transform: translateY(0);
}

.modal-header {
  padding: 18px 24px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-size: 1.15rem;
  font-weight: 700;
}

.modal-close {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-secondary);
}

.modal-close:hover {
  color: var(--text-primary);
}

.modal-body {
  padding: 24px;
}

.modal-footer {
  padding: 16px 24px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: flex-end;
  gap: 12px;
}

/* Toast Notification Stack */
#toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 9999;
}

.toast {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 20px;
  border-radius: var(--border-radius-md);
  color: white;
  font-size: 0.85rem;
  font-weight: 500;
  box-shadow: var(--shadow-lg);
  min-width: 250px;
  max-width: 350px;
  animation: slideIn 0.3s cubic-bezier(0.4, 0, 0.2, 1) forwards;
  position: relative;
  overflow: hidden;
}

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

.toast.toast-success { background-color: var(--success); }
.toast.toast-danger { background-color: var(--danger); }
.toast.toast-warning { background-color: var(--warning); color: #1e293b; }
.toast.toast-info { background-color: var(--info); }

.toast-progress {
  position: absolute;
  bottom: 0;
  left: 0;
  height: 3px;
  background-color: rgba(255, 255, 255, 0.4);
  width: 100%;
  animation: progress linear forwards;
}

@keyframes progress {
  from { width: 100%; }
  to { width: 0%; }
}

/* Pagination */
.pagination {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px;
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-radius: 0 0 var(--border-radius-md) var(--border-radius-md);
}

.pagination-buttons {
  display: flex;
  gap: 8px;
}

/* Empty States */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 40px;
  text-align: center;
  color: var(--text-muted);
}

.empty-state svg {
  width: 48px;
  height: 48px;
  margin-bottom: 16px;
}

/* Responsive Grid/Flex adjustments */
@media (max-width: 1024px) {
  #app-container {
    grid-template-columns: 1fr;
    grid-template-rows: 70px 1fr;
    grid-template-areas:
      "topbar"
      "main";
  }
  
  #sidebar {
    position: fixed;
    left: -260px;
    top: 70px;
    bottom: 0;
    width: 260px;
    transition: left var(--transition-normal);
    z-index: 100;
  }
  
  #sidebar.open {
    left: 0;
  }
  
  .hamburger-btn {
    display: flex; /* Show toggle on mobile/tablet */
  }

  .btn-sm {
    padding: 8px 12px;
    font-size: 0.85rem;
    min-height: 44px; /* Enlarge button target for touch screens */
  }
  
  .grid-cols-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-cols-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-cols-1-2 { grid-template-columns: 1fr; }
  .grid-cols-2-1 { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  #topbar {
    padding: 0 16px;
  }
  
  .topbar-right {
    gap: 8px;
  }
  
  .topbar-actions {
    gap: 6px;
  }
  
  .breadcrumb-title {
    font-size: 1.1rem;
    display: none; /* Hide title on smaller screens to save space */
  }
  
  .system-time {
    display: none; /* Hide clock on tablets and mobile to save space */
  }
  
  .user-selector-container label {
    display: none; /* Hide labels to save space */
  }
  
  .user-select {
    max-width: 120px;
    font-size: 0.8rem;
  }
  
  .grid-cols-4, .grid-cols-3, .grid-cols-2 {
    grid-template-columns: 1fr;
  }
  
  .form-row {
    grid-template-columns: 1fr;
  }
  
  .filters-bar {
    flex-direction: column;
    align-items: stretch;
  }
}

@media (max-width: 480px) {
  #main-viewport {
    padding: 16px;
    gap: 16px;
  }
  
  #topbar {
    padding: 0 8px;
  }
  
  .topbar-left {
    gap: 6px;
  }

  .topbar-right {
    gap: 4px;
  }
  
  .theme-toggle, .notification-bell {
    width: 32px;
    height: 32px;
    min-width: 32px;
  }
  
  .user-select {
    max-width: 90px;
    min-width: 0;
    padding: 6px 4px;
    font-size: 0.75rem;
  }
  
  #global-channel-select {
    display: none; /* Hide active channel selector on phones completely to fit country and profile */
  }
  
  .stat-card {
    padding: 16px;
    min-height: auto;
  }
  
  .stat-value {
    font-size: 1.4rem;
  }
  
  .modal-container {
    width: 95%;
  }
  
  .modal-body {
    padding: 16px;
  }
  
  .modal-footer {
    padding: 12px 16px;
    flex-direction: column;
  }
  
  .modal-footer .btn {
    width: 100%;
    margin: 0 0 8px 0;
  }
}


/* Login Page Overlay & Container styling */
.login-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: var(--bg-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 99999;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.login-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.login-container {
  width: 90%;
  max-width: 400px;
  padding: 40px 30px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  border: 1px solid var(--border-color);
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-xl);
}

.login-logo {
  width: 100px;
  height: 100px;
  object-fit: contain;
  margin-bottom: 16px;
}