/**
 * ASTRA AI Gateway - Professional Design System
 * Version: 4.0
 * Theme: Professional Dark (2026 UI Trends)
 *
 * Features:
 * - AI-driven adaptive layouts
 * - Glassmorphism effects
 * - Smooth animations
 * - WCAG 2.1 AA accessible
 * - Mobile-first responsive
 */

/* ============================================
   CSS CUSTOM PROPERTIES (VARIABLES)
   ============================================ */

:root {
  /* === Primary Colors === */
  --color-bg-primary: #0a0a1a;
  --color-bg-secondary: #12122a;
  --color-bg-tertiary: #1a1a3e;
  --color-bg-elevated: #1e1e4a;
  --color-bg-card: rgba(26, 26, 62, 0.7);
  --color-bg-card-hover: rgba(30, 30, 74, 0.9);

  /* === Accent Colors === */
  --color-accent-primary: #6366f1;
  --color-accent-primary-hover: #818cf8;
  --color-accent-primary-glow: rgba(99, 102, 241, 0.4);

  --color-accent-success: #10b981;
  --color-accent-success-glow: rgba(16, 185, 129, 0.4);

  --color-accent-warning: #f59e0b;
  --color-accent-warning-glow: rgba(245, 158, 11, 0.4);

  --color-accent-danger: #ef4444;
  --color-accent-danger-glow: rgba(239, 68, 68, 0.5);

  --color-accent-info: #3b82f6;
  --color-accent-info-glow: rgba(59, 130, 246, 0.4);

  --color-accent-purple: #a855f7;
  --color-accent-cyan: #06b6d4;

  /* === Text Colors === */
  --color-text-primary: #f8fafc;
  --color-text-secondary: #94a3b8;
  --color-text-muted: #64748b;
  --color-text-disabled: #475569;

  /* === Border Colors === */
  --color-border: rgba(148, 163, 184, 0.1);
  --color-border-hover: rgba(148, 163, 184, 0.2);
  --color-border-focus: var(--color-accent-primary);

  /* === Gradients === */
  --gradient-primary: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
  --gradient-success: linear-gradient(135deg, #10b981 0%, #06b6d4 100%);
  --gradient-danger: linear-gradient(135deg, #ef4444 0%, #f97316 100%);
  --gradient-dark: linear-gradient(180deg, #0a0a1a 0%, #12122a 100%);
  --gradient-card: linear-gradient(135deg, rgba(26, 26, 62, 0.8) 0%, rgba(30, 30, 74, 0.6) 100%);
  --gradient-glow: radial-gradient(ellipse at center, var(--color-accent-primary-glow) 0%, transparent 70%);

  /* === Shadows === */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.6);
  --shadow-glow-primary: 0 0 20px var(--color-accent-primary-glow);
  --shadow-glow-success: 0 0 20px var(--color-accent-success-glow);
  --shadow-glow-danger: 0 0 20px var(--color-accent-danger-glow);

  /* === Spacing === */
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1.25rem;
  --space-lg: 2rem;
  --space-xl: 2.5rem;
  --space-2xl: 4rem;
  --space-3xl: 5rem;

  /* Spacing aliases for compatibility */
  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1.25rem;
  --spacing-lg: 2rem;
  --spacing-xl: 2.5rem;
  --spacing-2xl: 4rem;
  --spacing-3xl: 5rem;

  /* === Typography === */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-md: 0.9375rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;

  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;

  /* === Border Radius === */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* === Transitions === */
  --transition-fast: 150ms ease;
  --transition-normal: 200ms ease;
  --transition-slow: 300ms ease;
  --transition-bounce: 400ms cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* === Z-Index === */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-modal: 300;
  --z-tooltip: 400;
  --z-notification: 500;

  /* === Container === */
  --container-max: 1400px;
  --sidebar-width: 280px;
  --header-height: 64px;
}

/* ============================================
   BASE STYLES
   ============================================ */

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text-primary);
  background: var(--gradient-dark);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--color-border-hover);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-muted);
}

/* Selection */
::selection {
  background: var(--color-accent-primary);
  color: white;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */

h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-tight);
  color: var(--color-text-primary);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

p {
  color: var(--color-text-secondary);
  margin-bottom: var(--space-md);
}

a {
  color: var(--color-accent-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-accent-primary-hover);
}

code, pre {
  font-family: var(--font-family-mono);
  font-size: var(--font-size-sm);
}

code {
  background: var(--color-bg-tertiary);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
  color: var(--color-accent-cyan);
}

pre {
  background: var(--color-bg-tertiary);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  overflow-x: auto;
  border: 1px solid var(--color-border);
}

/* ============================================
   LAYOUT COMPONENTS
   ============================================ */

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.page-wrapper {
  display: flex;
  min-height: 100vh;
}

.main-content {
  flex: 1;
  margin-left: var(--sidebar-width);
  padding: var(--space-xl);
  padding-top: calc(var(--header-height) + var(--space-xl));
}

.grid {
  display: grid;
  gap: var(--space-lg);
}

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

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

@media (max-width: 768px) {
  .main-content {
    margin-left: 0;
    padding: var(--space-md);
  }
  .grid-cols-2, .grid-cols-3, .grid-cols-4 {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   CARD COMPONENT
   ============================================ */

.card {
  background: var(--gradient-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-lg);
  transition: all var(--transition-normal);
}

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

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

.card-title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
}

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

.card-body {
  flex: 1;
}

/* Card spacing utilities */
.card + .card {
  margin-top: var(--space-lg);
}

section + section,
.section + .section {
  margin-top: var(--space-xl);
}

.card-footer {
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
}

/* Stat Card */
.stat-card {
  position: relative;
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 100px;
  height: 100px;
  background: var(--gradient-glow);
  opacity: 0.3;
  border-radius: 50%;
  transform: translate(30%, -30%);
}

.stat-value {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  line-height: 1;
}

.stat-label {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-top: var(--space-xs);
}

.stat-trend {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: var(--font-size-sm);
  margin-top: var(--space-sm);
}

.stat-trend.up { color: var(--color-accent-success); }
.stat-trend.down { color: var(--color-accent-danger); }

/* ============================================
   BUTTON COMPONENT
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  font-family: var(--font-family);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
  white-space: nowrap;
}

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

/* Primary Button */
.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-glow-primary);
}

.btn-primary:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 0 30px var(--color-accent-primary-glow);
}

/* Success Button */
.btn-success {
  background: var(--gradient-success);
  color: white;
  box-shadow: var(--shadow-glow-success);
}

.btn-success:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 0 30px var(--color-accent-success-glow);
}

/* Danger Button */
.btn-danger {
  background: var(--gradient-danger);
  color: white;
  box-shadow: var(--shadow-glow-danger);
}

.btn-danger:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 0 30px var(--color-accent-danger-glow);
}

/* Ghost Button */
.btn-ghost {
  background: transparent;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
}

.btn-ghost:hover:not(:disabled) {
  background: var(--color-bg-tertiary);
  border-color: var(--color-border-hover);
  color: var(--color-text-primary);
}

/* Icon Button */
.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: var(--radius-md);
}

/* Button Sizes */
.btn-sm {
  padding: var(--space-xs) var(--space-md);
  font-size: var(--font-size-xs);
}

.btn-lg {
  padding: var(--space-md) var(--space-xl);
  font-size: var(--font-size-base);
}

/* Kill Switch Button (Special) */
.btn-kill-switch {
  background: var(--color-accent-danger);
  color: white;
  padding: var(--space-md) var(--space-xl);
  font-weight: var(--font-weight-bold);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  animation: pulse-danger 2s infinite;
}

.btn-kill-switch:hover {
  animation: none;
  box-shadow: 0 0 40px var(--color-accent-danger-glow);
}

@keyframes pulse-danger {
  0%, 100% { box-shadow: 0 0 20px var(--color-accent-danger-glow); }
  50% { box-shadow: 0 0 40px var(--color-accent-danger-glow); }
}

/* ============================================
   FORM COMPONENTS
   ============================================ */

.form-group {
  margin-bottom: var(--space-lg);
}

.form-label {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text-primary);
  background: var(--color-bg-tertiary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-accent-primary);
  box-shadow: 0 0 0 3px var(--color-accent-primary-glow);
}

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

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

/* Toggle Switch */
.toggle {
  position: relative;
  width: 48px;
  height: 24px;
}

.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-bg-tertiary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  transition: var(--transition-normal);
}

.toggle-slider::before {
  content: '';
  position: absolute;
  height: 18px;
  width: 18px;
  left: 2px;
  bottom: 2px;
  background: var(--color-text-muted);
  border-radius: 50%;
  transition: var(--transition-normal);
}

.toggle input:checked + .toggle-slider {
  background: var(--color-accent-primary);
  border-color: var(--color-accent-primary);
}

.toggle input:checked + .toggle-slider::before {
  background: white;
  transform: translateX(24px);
}

/* ============================================
   BADGE COMPONENT
   ============================================ */

.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-xs) var(--space-sm);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-primary {
  background: rgba(99, 102, 241, 0.2);
  color: var(--color-accent-primary);
}

.badge-success {
  background: rgba(16, 185, 129, 0.2);
  color: var(--color-accent-success);
}

.badge-warning {
  background: rgba(245, 158, 11, 0.2);
  color: var(--color-accent-warning);
}

.badge-danger {
  background: rgba(239, 68, 68, 0.2);
  color: var(--color-accent-danger);
}

.badge-info {
  background: rgba(59, 130, 246, 0.2);
  color: var(--color-accent-info);
}

/* Status Indicator */
.status-indicator {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.status-dot.active {
  background: var(--color-accent-success);
  box-shadow: 0 0 8px var(--color-accent-success-glow);
  animation: pulse-dot 2s infinite;
}

.status-dot.inactive {
  background: var(--color-text-muted);
}

.status-dot.warning {
  background: var(--color-accent-warning);
  box-shadow: 0 0 8px var(--color-accent-warning-glow);
}

.status-dot.danger {
  background: var(--color-accent-danger);
  box-shadow: 0 0 8px var(--color-accent-danger-glow);
  animation: pulse-dot 1s infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

/* ============================================
   TABLE COMPONENT
   ============================================ */

.table-container {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
}

.table {
  width: 100%;
  border-collapse: collapse;
}

.table th,
.table td {
  padding: var(--space-md);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.table th {
  background: var(--color-bg-tertiary);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  position: sticky;
  top: 0;
}

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

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

/* ============================================
   SIDEBAR COMPONENT
   ============================================ */

.sidebar {
  position: fixed;
  left: 0;
  top: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--color-bg-secondary);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  z-index: var(--z-sticky);
}

.sidebar-header {
  padding: var(--space-lg);
  border-bottom: 1px solid var(--color-border);
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.sidebar-logo img {
  width: 40px;
  height: 40px;
}

.sidebar-logo-text {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.sidebar-nav {
  flex: 1;
  padding: var(--space-md);
  overflow-y: auto;
}

.nav-section {
  margin-bottom: var(--space-lg);
}

.nav-section-title {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: var(--space-sm) var(--space-md);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  color: var(--color-text-secondary);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  margin-bottom: var(--space-xs);
}

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

.nav-item.active {
  background: rgba(99, 102, 241, 0.1);
  color: var(--color-accent-primary);
  border-left: 3px solid var(--color-accent-primary);
}

.nav-item-icon {
  width: 20px;
  height: 20px;
  opacity: 0.7;
}

.nav-item.active .nav-item-icon {
  opacity: 1;
}

/* ============================================
   HEADER COMPONENT
   ============================================ */

.header {
  position: fixed;
  top: 0;
  left: var(--sidebar-width);
  right: 0;
  height: var(--header-height);
  background: rgba(10, 10, 26, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-xl);
  z-index: var(--z-sticky);
}

.header-title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* ============================================
   ALERT/NOTIFICATION COMPONENT
   ============================================ */

.alert {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-md);
}

.alert-info {
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: var(--color-accent-info);
}

.alert-success {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: var(--color-accent-success);
}

.alert-warning {
  background: rgba(245, 158, 11, 0.1);
  border: 1px solid rgba(245, 158, 11, 0.3);
  color: var(--color-accent-warning);
}

.alert-danger {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: var(--color-accent-danger);
}

/* ============================================
   MODAL COMPONENT
   ============================================ */

/* Pattern 1: .modal-overlay > .modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal-overlay .modal {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  overflow: hidden;
  transform: scale(0.9) translateY(20px);
  transition: transform var(--transition-normal);
}

.modal-overlay.active .modal {
  transform: scale(1) translateY(0);
}

/* Pattern 2: .modal as overlay with .modal-content inside */
.modal {
  position: fixed;
  inset: 0;
  z-index: var(--z-modal);
  display: none;
  align-items: center;
  justify-content: center;
}

.modal.active {
  display: flex;
}

.modal .modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(4px);
}

.modal .modal-content {
  position: relative;
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 560px;
  max-height: 90vh;
  overflow: hidden;
  transform: scale(0.95);
  transition: transform var(--transition-normal);
  z-index: 1;
}

.modal.active .modal-content {
  transform: scale(1);
}

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

.modal-title {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
}

.modal-title i {
  color: var(--color-accent-primary);
}

.modal-close {
  background: transparent;
  border: none;
  color: var(--color-text-muted);
  cursor: pointer;
  padding: var(--space-sm);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

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

.modal-body {
  padding: var(--space-lg);
  overflow-y: auto;
  max-height: calc(90vh - 140px);
}

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

/* ============================================
   LOADING/SKELETON COMPONENT
   ============================================ */

.skeleton {
  background: linear-gradient(
    90deg,
    var(--color-bg-tertiary) 25%,
    var(--color-bg-elevated) 50%,
    var(--color-bg-tertiary) 75%
  );
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton-text {
  height: 1em;
  margin-bottom: var(--space-sm);
}

.skeleton-title {
  height: 1.5em;
  width: 60%;
}

.skeleton-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
}

/* ============================================
   PROGRESS BAR COMPONENT
   ============================================ */

.progress {
  height: 8px;
  background: var(--color-bg-tertiary);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

.progress-bar.success { background: var(--gradient-success); }
.progress-bar.danger { background: var(--gradient-danger); }

/* ============================================
   UTILITY CLASSES
   ============================================ */

/* Flexbox */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }
.flex-1 { flex: 1; }
.flex-wrap { flex-wrap: wrap; }

/* Spacing */
.m-0 { margin: 0; }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.p-md { padding: var(--space-md); }
.p-lg { padding: var(--space-lg); }

/* Text */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-sm { font-size: var(--font-size-sm); }
.text-lg { font-size: var(--font-size-lg); }
.text-muted { color: var(--color-text-muted); }
.text-primary { color: var(--color-accent-primary); }
.text-success { color: var(--color-accent-success); }
.text-warning { color: var(--color-accent-warning); }
.text-danger { color: var(--color-accent-danger); }
.font-semibold { font-weight: var(--font-weight-semibold); }
.font-bold { font-weight: var(--font-weight-bold); }

/* Visibility */
.hidden { display: none !important; }
.visible { visibility: visible; }
.invisible { visibility: hidden; }

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}

.animate-fadeIn { animation: fadeIn var(--transition-slow) ease; }
.animate-slideUp { animation: slideUp var(--transition-slow) ease; }
.animate-slideIn { animation: slideIn var(--transition-slow) ease; }

/* Staggered animations for lists */
.stagger-animation > *:nth-child(1) { animation-delay: 0ms; }
.stagger-animation > *:nth-child(2) { animation-delay: 50ms; }
.stagger-animation > *:nth-child(3) { animation-delay: 100ms; }
.stagger-animation > *:nth-child(4) { animation-delay: 150ms; }
.stagger-animation > *:nth-child(5) { animation-delay: 200ms; }