:root {
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
  --primary: #1976d2;
  --primary-rgb: 25, 118, 210;
  --primary-hover: #1565c0;
  --primary-container: #e3f2fd;
  --on-primary-container: #0d47a1;
  --secondary: #00796b;
  --secondary-container: #e0f2f1;
  --on-secondary-container: #004d40;
  --surface: #ffffff;
  --surface-variant: #f4f6f8;
  --background: #f8fafc;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --border-strong: #cbd5e1;
  --error: #d32f2f;
  --error-container: #ffebee;
  --on-error-container: #b71c1c;
  --success: #2e7d32;
  --success-container: #e8f5e9;
  --warning: #ed6c02;
  --warning-container: #fff3e0;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --sidebar-width: 260px;
}

[data-theme="dark"] {
  --primary: #90caf9;
  --primary-hover: #bbdefb;
  --primary-container: #1e3a5f;
  --on-primary-container: #e3f2fd;
  --secondary: #80cbc4;
  --secondary-container: #1b4d45;
  --on-secondary-container: #e0f2f1;
  --surface: #1e293b;
  --surface-variant: #334155;
  --background: #0f172a;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --border: #334155;
  --border-strong: #475569;
  --error: #ef5350;
  --error-container: #451517;
  --on-error-container: #ffcdd2;
  --success: #66bb6a;
  --success-container: #1b4522;
  --warning: #ffa726;
  --warning-container: #482c0a;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-family);
  background-color: var(--background);
  color: var(--text-main);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

[dir="rtl"] {
  text-align: right;
}

a {
  color: var(--primary);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
}

/* Layout */
#app-root {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.app-layout {
  display: flex;
  min-height: 100vh;
}

.app-sidebar {
  width: var(--sidebar-width);
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  z-index: 40;
  transition: transform 0.25s ease-in-out;
}

[dir="rtl"] .app-sidebar {
  left: auto;
  right: 0;
  border-right: none;
  border-left: 1px solid var(--border);
}

.app-main {
  flex: 1;
  margin-left: var(--sidebar-width);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  padding-bottom: 70px; /* Space for mobile nav */
}

[dir="rtl"] .app-main {
  margin-left: 0;
  margin-right: var(--sidebar-width);
}

.top-bar {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 12px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 30;
}

.content-container {
  padding: 24px;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

/* Mobile Sidebar Drawer Overlay */
.drawer-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 35;
}

/* Cards & Surfaces */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 20px;
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.card-title {
  font-size: 1.15rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* Typography & Badges */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.badge-primary { background: var(--primary-container); color: var(--on-primary-container); }
.badge-secondary { background: var(--secondary-container); color: var(--on-secondary-container); }
.badge-success { background: var(--success-container); color: var(--success); }
.badge-error { background: var(--error-container); color: var(--error); }
.badge-warning { background: var(--warning-container); color: var(--warning); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: var(--radius-md);
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.btn-sm {
  padding: 6px 12px;
  font-size: 0.825rem;
}

.btn-primary {
  background: var(--primary);
  color: #ffffff;
}
.btn-primary:hover {
  background: var(--primary-hover);
  text-decoration: none;
}

.btn-secondary {
  background: var(--secondary);
  color: #ffffff;
}

.btn-outline {
  background: transparent;
  border-color: var(--border-strong);
  color: var(--text-main);
}
.btn-outline:hover {
  background: var(--surface-variant);
  text-decoration: none;
}

.btn-danger {
  background: var(--error);
  color: #ffffff;
}

.btn-block {
  width: 100%;
}

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

/* Form inputs */
.form-group {
  margin-bottom: 16px;
  text-align: left;
}

[dir="rtl"] .form-group {
  text-align: right;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-main);
}

.form-control {
  width: 100%;
  padding: 10px 14px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-strong);
  background: var(--surface);
  color: var(--text-main);
  transition: border-color 0.15s ease;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(var(--primary-rgb), 0.15);
}

/* Grid & Tables */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.table-responsive {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface);
}

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

[dir="rtl"] .data-table {
  text-align: right;
}

.data-table th, .data-table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
}

.data-table th {
  background: var(--surface-variant);
  font-weight: 700;
  color: var(--text-muted);
}

.data-table tr:hover {
  background: var(--surface-variant);
}

/* Mobile Bottom Navigation */
.mobile-bottom-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 64px;
  background: var(--surface);
  border-top: 1px solid var(--border);
  z-index: 50;
  justify-content: space-around;
  align-items: center;
}

.bottom-nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  font-size: 0.75rem;
  color: var(--text-muted);
  gap: 2px;
}

.bottom-nav-item.active {
  color: var(--primary);
  font-weight: 700;
}

/* Modals */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 16px;
}

.modal-content {
  background: var(--surface);
  border-radius: var(--radius-lg);
  max-width: 600px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  padding: 24px;
  box-shadow: var(--shadow-lg);
}

/* Notification Banners */
.alert {
  padding: 12px 16px;
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 12px;
}

.alert-warning { background: var(--warning-container); color: var(--warning); border: 1px solid var(--warning); }
.alert-error { background: var(--error-container); color: var(--error); border: 1px solid var(--error); }
.alert-success { background: var(--success-container); color: var(--success); border: 1px solid var(--success); }

/* Update Banner */
#update-banner {
  display: none;
  position: fixed;
  top: 10px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: white;
  padding: 10px 20px;
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-lg);
  z-index: 200;
  align-items: center;
  gap: 12px;
}

/* Media Queries for Mobile Responsiveness */
@media (max-width: 768px) {
  .app-sidebar {
    transform: translateX(-100%);
  }
  [dir="rtl"] .app-sidebar {
    transform: translateX(100%);
  }
  .app-sidebar.open {
    transform: translateX(0);
  }
  .drawer-backdrop.open {
    display: block;
  }
  .app-main {
    margin-left: 0;
    margin-right: 0;
  }
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
  .mobile-bottom-nav {
    display: flex;
  }
}