:root {
  --bg-main: #0f172a;
  --bg-surface: #1e293b;
  --bg-card: #24344d;
  --bg-input: #0b1120;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --primary: #3b82f6;
  --primary-hover: #2563eb;
  --accent: #6366f1;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --border: #334155;
  --border-focus: #60a5fa;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -2px rgba(0, 0, 0, 0.3);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background-color: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.5;
  min-height: 100vh;
}

/* Layout */
.app-container {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 260px;
  background-color: var(--bg-surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
}

.sidebar-header {
  padding: 24px 20px;
  border-bottom: 1px solid var(--border);
}

.brand-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary);
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 4px;
}

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

.nav-link {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  border-radius: 8px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s ease;
}

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

.nav-link.active {
  background-color: rgba(59, 130, 246, 0.15);
  color: var(--primary);
  border-left: 3px solid var(--primary);
}

.sidebar-footer {
  padding: 16px 20px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Main Content */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.top-bar {
  height: 64px;
  background-color: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 32px;
}

.page-title {
  font-size: 1.25rem;
  font-weight: 600;
}

.content-body {
  padding: 32px;
}

/* Cards & Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
  margin-bottom: 32px;
}

.stat-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  box-shadow: var(--shadow);
}

.stat-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-muted);
  text-transform: uppercase;
  font-weight: 600;
  letter-spacing: 0.05em;
}

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

.stat-desc {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 6px;
}

.card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: var(--shadow);
}

.card-title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* Tables */
.table-container {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.9rem;
}

th {
  background-color: var(--bg-card);
  color: var(--text-secondary);
  padding: 12px 16px;
  font-weight: 600;
  border-bottom: 1px solid var(--border);
}

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

tr:hover td {
  background-color: rgba(255, 255, 255, 0.02);
}

/* Badges */
.badge {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
}

.badge-success { background: rgba(16, 185, 129, 0.15); color: var(--success); }
.badge-warning { background: rgba(245, 158, 11, 0.15); color: var(--warning); }
.badge-danger { background: rgba(239, 68, 68, 0.15); color: var(--danger); }
.badge-info { background: rgba(59, 130, 246, 0.15); color: var(--primary); }
.badge-neutral { background: rgba(148, 163, 184, 0.15); color: var(--text-secondary); }

/* Forms & Buttons */
.form-group {
  margin-bottom: 18px;
}

label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

input, select, textarea {
  width: 100%;
  padding: 10px 14px;
  background-color: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.2s;
}

input:focus, select:focus, textarea:focus {
  border-color: var(--border-focus);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 500;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s ease;
}

.btn-primary {
  background-color: var(--primary);
  color: #fff;
}
.btn-primary:hover { background-color: var(--primary-hover); }

.btn-secondary {
  background-color: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border);
}
.btn-secondary:hover { background-color: var(--border); }

.btn-danger {
  background-color: var(--danger);
  color: #fff;
}
.btn-sm {
  padding: 6px 12px;
  font-size: 0.8rem;
}

/* Alerts */
.alert {
  padding: 14px 18px;
  border-radius: 8px;
  font-size: 0.9rem;
  margin-bottom: 20px;
}
.alert-success { background: rgba(16, 185, 129, 0.15); border: 1px solid var(--success); color: #6ee7b7; }
.alert-danger { background: rgba(239, 68, 68, 0.15); border: 1px solid var(--danger); color: #fca5a5; }

/* Login Page */
.login-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background-color: var(--bg-main);
  padding: 20px;
}

.login-card {
  width: 100%;
  max-width: 420px;
  background-color: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 36px;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.5);
}