/* ============================================
   SAAS PLATFORM - DESIGN SYSTEM
   Dark Theme Modern UI
   ============================================ */

/* --- CSS RESET & BASE --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Background layers */
  --bg-primary: #06080d;
  --bg-secondary: #0c1017;
  --bg-tertiary: #111827;
  --bg-card: rgba(17, 24, 39, 0.6);
  --bg-card-hover: rgba(17, 24, 39, 0.85);
  --bg-glass: rgba(15, 23, 42, 0.65);
  --bg-input: rgba(15, 23, 42, 0.5);
  --bg-input-focus: rgba(15, 23, 42, 0.8);

  /* Borders */
  --border-subtle: rgba(148, 163, 184, 0.08);
  --border-default: rgba(148, 163, 184, 0.12);
  --border-hover: rgba(148, 163, 184, 0.2);
  --border-focus: rgba(99, 102, 241, 0.5);

  /* Text */
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-inverse: #0f172a;

  /* Accent colors */
  --accent: #6366f1;
  --accent-hover: #818cf8;
  --accent-glow: rgba(99, 102, 241, 0.25);
  --accent-subtle: rgba(99, 102, 241, 0.1);

  /* Semantic colors */
  --success: #10b981;
  --success-subtle: rgba(16, 185, 129, 0.1);
  --success-border: rgba(16, 185, 129, 0.3);
  --warning: #f59e0b;
  --warning-subtle: rgba(245, 158, 11, 0.1);
  --warning-border: rgba(245, 158, 11, 0.3);
  --danger: #ef4444;
  --danger-subtle: rgba(239, 68, 68, 0.1);
  --danger-border: rgba(239, 68, 68, 0.3);
  --info: #06b6d4;
  --info-subtle: rgba(6, 182, 212, 0.1);
  --info-border: rgba(6, 182, 212, 0.3);

  /* Gradients */
  --gradient-accent: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a78bfa 100%);
  --gradient-surface: linear-gradient(180deg, rgba(99, 102, 241, 0.03) 0%, transparent 100%);
  --gradient-glow: radial-gradient(ellipse at 50% 0%, rgba(99, 102, 241, 0.15) 0%, transparent 60%);

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.15);
  --shadow-glow-lg: 0 0 40px rgba(99, 102, 241, 0.2);

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 2rem;

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Z-index scale */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-modal-backdrop: 300;
  --z-modal: 400;
  --z-toast: 500;
}

/* --- FONT IMPORT --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Animated background mesh */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    radial-gradient(ellipse 80% 50% at 20% -10%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse 60% 40% at 80% 110%, rgba(139, 92, 246, 0.06) 0%, transparent 50%),
    radial-gradient(ellipse 40% 30% at 50% 50%, rgba(6, 182, 212, 0.03) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
}

/* --- TYPOGRAPHY --- */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.02em;
}

h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

p { color: var(--text-secondary); line-height: 1.7; }

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

/* --- SCROLLBAR --- */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
  background: rgba(148, 163, 184, 0.15);
  border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover { background: rgba(148, 163, 184, 0.25); }

/* --- SELECTION --- */
::selection {
  background: rgba(99, 102, 241, 0.3);
  color: var(--text-primary);
}

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

/* --- GLASS CARD --- */
.card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(148, 163, 184, 0.1), transparent);
}

.card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-md);
}

.card-glass {
  background: var(--bg-glass);
  backdrop-filter: blur(24px) saturate(150%);
  -webkit-backdrop-filter: blur(24px) saturate(150%);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

/* --- BUTTONS --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.65rem 1.4rem;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 500;
  line-height: 1;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  outline: none;
  white-space: nowrap;
  user-select: none;
  position: relative;
  overflow: hidden;
}

.btn:active { transform: scale(0.97); }

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* Primary */
.btn-primary {
  background: var(--gradient-accent);
  color: white;
  border: none;
  box-shadow: var(--shadow-sm), 0 0 0 0 var(--accent-glow);
}
.btn-primary:hover:not(:disabled) {
  box-shadow: var(--shadow-md), var(--shadow-glow);
  filter: brightness(1.1);
}

/* Secondary / Ghost */
.btn-secondary {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-default);
}
.btn-secondary:hover:not(:disabled) {
  background: var(--bg-card);
  color: var(--text-primary);
  border-color: var(--border-hover);
}

/* Danger */
.btn-danger {
  background: var(--danger-subtle);
  color: var(--danger);
  border: 1px solid var(--danger-border);
}
.btn-danger:hover:not(:disabled) {
  background: var(--danger);
  color: white;
}

/* Success */
.btn-success {
  background: var(--success-subtle);
  color: var(--success);
  border: 1px solid var(--success-border);
}
.btn-success:hover:not(:disabled) {
  background: var(--success);
  color: white;
}

/* Icon button */
.btn-icon {
  padding: 0.55rem;
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--text-muted);
  border: 1px solid transparent;
}
.btn-icon:hover { color: var(--text-primary); background: var(--bg-card); }

/* Loading state */
.btn-loading {
  pointer-events: none;
  color: transparent !important;
}
.btn-loading::after {
  content: '';
  position: absolute;
  width: 18px;
  height: 18px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* --- INPUTS --- */
.input-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.input-group label {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-secondary);
}

.input {
  width: 100%;
  padding: 0.7rem 1rem;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  color: var(--text-primary);
  background: var(--bg-input);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  outline: none;
  transition: all var(--transition-fast);
}

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

.input:focus {
  background: var(--bg-input-focus);
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

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

.input-error {
  border-color: var(--danger) !important;
  box-shadow: 0 0 0 3px var(--danger-subtle) !important;
}

.input-icon-wrapper {
  position: relative;
}
.input-icon-wrapper .input {
  padding-left: 2.8rem;
}
.input-icon-wrapper .icon {
  position: absolute;
  left: 1rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  width: 18px;
  height: 18px;
  pointer-events: none;
}

/* --- BADGES / TAGS --- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.2rem 0.65rem;
  font-size: var(--text-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
  letter-spacing: 0.02em;
}

.badge-accent { background: var(--accent-subtle); color: var(--accent-hover); }
.badge-success { background: var(--success-subtle); color: var(--success); }
.badge-warning { background: var(--warning-subtle); color: var(--warning); }
.badge-danger { background: var(--danger-subtle); color: var(--danger); }
.badge-info { background: var(--info-subtle); color: var(--info); }
.badge-muted { background: rgba(100, 116, 139, 0.15); color: var(--text-muted); }

/* Dot indicator */
.badge-dot::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

/* --- TOAST NOTIFICATIONS --- */
.toast-container {
  position: fixed;
  top: var(--space-lg);
  right: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  z-index: var(--z-toast);
  pointer-events: none;
}

.toast {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: 0.85rem 1.2rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  pointer-events: auto;
  animation: toastIn 0.35s ease-out;
  max-width: 380px;
}

.toast-success { border-left: 3px solid var(--success); }
.toast-error { border-left: 3px solid var(--danger); }
.toast-warning { border-left: 3px solid var(--warning); }
.toast-info { border-left: 3px solid var(--info); }

.toast-message {
  font-size: var(--text-sm);
  color: var(--text-primary);
}

.toast-close {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  font-size: 1.1rem;
  line-height: 1;
}

.toast.toast-exit {
  animation: toastOut 0.3s ease-in forwards;
}

@keyframes toastIn {
  from { opacity: 0; transform: translateX(30px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes toastOut {
  from { opacity: 1; transform: translateX(0); }
  to { opacity: 0; transform: translateX(30px); }
}

/* --- MODAL --- */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  z-index: var(--z-modal-backdrop);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-lg);
  animation: fadeIn 0.2s ease-out;
}

.modal {
  background: var(--bg-secondary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: var(--space-xl);
  width: 100%;
  max-width: 480px;
  max-height: 85vh;
  overflow-y: auto;
  z-index: var(--z-modal);
  animation: modalIn 0.3s ease-out;
  box-shadow: var(--shadow-lg);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-lg);
}

.modal-title {
  font-size: var(--text-lg);
  font-weight: 600;
}

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

@keyframes modalIn {
  from { opacity: 0; transform: scale(0.95) translateY(10px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}

/* --- TABLE --- */
.table-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
}

.table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
}

.table th {
  padding: 0.75rem 1rem;
  text-align: left;
  font-weight: 600;
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  background: var(--bg-tertiary);
  border-bottom: 1px solid var(--border-default);
}

.table td {
  padding: 0.75rem 1rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-subtle);
}

.table tr:last-child td { border-bottom: none; }

.table tr:hover td {
  background: rgba(99, 102, 241, 0.03);
}

/* --- SIDEBAR / NAV --- */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: 260px;
  height: 100vh;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  z-index: var(--z-sticky);
  transition: transform var(--transition-base);
}

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

.sidebar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--text-primary);
}

.sidebar-brand .brand-icon {
  width: 32px;
  height: 32px;
  background: var(--gradient-accent);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
}

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

.nav-section-title {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  padding: var(--space-md) var(--space-sm) var(--space-xs);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.6rem 0.8rem;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: 450;
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-bottom: 2px;
}

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

.nav-item.active {
  background: var(--accent-subtle);
  color: var(--accent-hover);
}

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

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

.sidebar-footer {
  padding: var(--space-md) var(--space-lg);
  border-top: 1px solid var(--border-subtle);
}

/* --- MAIN CONTENT --- */
.main-content {
  margin-left: 260px;
  padding: var(--space-xl);
  min-height: 100vh;
  position: relative;
  z-index: 1;
}

/* --- TOP BAR --- */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-xl);
}

.topbar-title h2 {
  font-size: var(--text-2xl);
}
.topbar-title p {
  font-size: var(--text-sm);
  color: var(--text-muted);
  margin-top: 0.15rem;
}

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

/* --- STATS GRID --- */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-md);
}

.stat-card {
  padding: var(--space-lg);
}

.stat-label {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: var(--space-xs);
}

.stat-value {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--text-primary);
}

.stat-change {
  display: inline-flex;
  align-items: center;
  gap: 0.2rem;
  font-size: var(--text-xs);
  font-weight: 500;
  margin-top: var(--space-xs);
}
.stat-change.positive { color: var(--success); }
.stat-change.negative { color: var(--danger); }

/* --- EMPTY STATE --- */
.empty-state {
  text-align: center;
  padding: var(--space-3xl) var(--space-xl);
}

.empty-state .empty-icon {
  font-size: 3rem;
  margin-bottom: var(--space-md);
  opacity: 0.4;
}

.empty-state h3 {
  font-size: var(--text-lg);
  margin-bottom: var(--space-xs);
}

.empty-state p {
  font-size: var(--text-sm);
  color: var(--text-muted);
  max-width: 360px;
  margin: 0 auto var(--space-lg);
}

/* --- LOADER --- */
.loader {
  width: 32px;
  height: 32px;
  border: 3px solid var(--border-default);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

.loader-sm {
  width: 18px;
  height: 18px;
  border-width: 2px;
}

/* Page loader overlay */
.page-loader {
  position: fixed;
  inset: 0;
  background: var(--bg-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  transition: opacity var(--transition-slow);
}

.page-loader.fade-out {
  opacity: 0;
  pointer-events: none;
}

/* --- DIVIDER --- */
.divider {
  height: 1px;
  background: var(--border-subtle);
  margin: var(--space-lg) 0;
}

.divider-text {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  color: var(--text-muted);
  font-size: var(--text-sm);
}
.divider-text::before,
.divider-text::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border-subtle);
}

/* --- AVATAR --- */
.avatar {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background: var(--gradient-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-sm);
  font-weight: 600;
  color: white;
  flex-shrink: 0;
}

.avatar-sm { width: 28px; height: 28px; font-size: var(--text-xs); }
.avatar-lg { width: 48px; height: 48px; font-size: var(--text-lg); }

/* --- DROPDOWN --- */
.dropdown {
  position: relative;
}

.dropdown-menu {
  position: absolute;
  top: calc(100% + 4px);
  right: 0;
  min-width: 200px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: var(--space-xs);
  z-index: var(--z-dropdown);
  display: none;
  animation: dropIn 0.15s ease-out;
}

.dropdown-menu.show { display: block; }

.dropdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.55rem 0.8rem;
  font-size: var(--text-sm);
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}
.dropdown-item:hover {
  background: var(--bg-card);
  color: var(--text-primary);
}

@keyframes dropIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* --- SKELETON LOADER --- */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--bg-card) 25%,
    rgba(148, 163, 184, 0.06) 50%,
    var(--bg-card) 75%
  );
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
  border-radius: var(--radius-sm);
}

.skeleton-text { height: 14px; margin-bottom: 8px; }
.skeleton-title { height: 24px; width: 60%; margin-bottom: 12px; }
.skeleton-circle { border-radius: 50%; }

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

/* --- UTILITIES --- */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-xs { gap: var(--space-xs); }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }
.gap-xl { gap: var(--space-xl); }

.text-center { text-align: center; }
.text-sm { font-size: var(--text-sm); }
.text-xs { font-size: var(--text-xs); }
.text-muted { color: var(--text-muted); }
.text-accent { color: var(--accent); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }
.font-mono { font-family: var(--font-mono); }
.font-bold { font-weight: 700; }
.font-medium { font-weight: 500; }

.w-full { width: 100%; }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }

.hidden { display: none !important; }
.visible { display: block !important; }

/* --- RESPONSIVE --- */
@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-left: 0; }
  .stats-grid { grid-template-columns: 1fr; }
}