:root {
  --primary: #1e40af;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --secondary: #475569;
  --success: #059669;
  --success-light: #ecfdf5;
  --warning: #d97706;
  --warning-light: #fffbeb;
  --danger: #dc2626;
  --danger-light: #fef2f2;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --text: #0f172a;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --radius: 10px;
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.05), 0 2px 4px -2px rgb(0 0 0 / 0.05);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.08), 0 4px 6px -4px rgb(0 0 0 / 0.05);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, Roboto, sans-serif;
}

body {
  background-color: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.navbar {
  background: #ffffff;
  border-bottom: 1px solid var(--border);
  padding: 0.75rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}

.brand-badge {
  background: #dbeafe;
  color: var(--primary);
  font-size: 0.75rem;
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  font-weight: 600;
}

.device-status-pill {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.9rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 9999px;
  font-size: 0.85rem;
  font-weight: 500;
}

.status-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #94a3b8;
}

.status-dot.online {
  background: #10b981;
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.25);
}

.status-dot.offline {
  background: #ef4444;
}

.app-container {
  display: flex;
  flex: 1;
}

.sidebar {
  width: 250px;
  background: #ffffff;
  border-right: 1px solid var(--border);
  padding: 1.5rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  color: var(--secondary);
  text-decoration: none;
  border-radius: var(--radius);
  font-weight: 500;
  font-size: 0.95rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.nav-item:hover {
  background: var(--primary-light);
  color: var(--primary);
}

.nav-item.active {
  background: var(--primary);
  color: #ffffff;
}

.nav-item i {
  width: 20px;
  text-align: center;
}

.main-content {
  flex: 1;
  padding: 2rem;
  overflow-y: auto;
  max-width: 1400px;
}

.tab-pane {
  display: none;
}

.tab-pane.active {
  display: block;
  animation: fadeIn 0.2s ease-in-out;
}

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

.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.25rem;
  margin-bottom: 2rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.25rem;
  margin-bottom: 2rem;
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

.card-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.stat-card {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.stat-icon {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.stat-icon.blue { background: #dbeafe; color: #1d4ed8; }
.stat-icon.green { background: #dcfce7; color: #15803d; }
.stat-icon.amber { background: #fef3c7; color: #b45309; }
.stat-icon.purple { background: #f3e8ff; color: #7e22ce; }

.stat-value {
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1.2;
}

.stat-label {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-top: 0.2rem;
}

.table-container {
  background: var(--card-bg);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  overflow-x: auto;
  margin-bottom: 1.5rem;
}

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

th {
  background: #f8fafc;
  padding: 0.85rem 1rem;
  font-weight: 600;
  color: var(--secondary);
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

td {
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  vertical-align: middle;
}

tr:hover td {
  background-color: #f8fafc;
}

.badge {
  display: inline-block;
  padding: 0.25rem 0.6rem;
  border-radius: 6px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge-success { background: #dcfce7; color: #166534; }
.badge-warning { background: #fef3c7; color: #92400e; }
.badge-danger { background: #fee2e2; color: #991b1b; }
.badge-info { background: #dbeafe; color: #1e40af; }
.badge-gray { background: #f1f5f9; color: #475569; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s;
  text-decoration: none;
}

.btn-primary { background: var(--primary); color: #ffffff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-success { background: var(--success); color: #ffffff; }
.btn-success:hover { background: #047857; }
.btn-outline { background: #ffffff; border-color: var(--border); color: var(--text); }
.btn-outline:hover { background: var(--bg); border-color: #cbd5e1; }
.btn-sm { padding: 0.35rem 0.65rem; font-size: 0.8rem; border-radius: 6px; }
.btn-group { display: flex; gap: 0.5rem; flex-wrap: wrap; }

.form-group { margin-bottom: 1.1rem; }
.form-label { display: block; font-size: 0.85rem; font-weight: 600; margin-bottom: 0.35rem; color: var(--secondary); }
.form-control { width: 100%; padding: 0.6rem 0.85rem; border: 1px solid var(--border); border-radius: var(--radius); font-size: 0.9rem; background: #ffffff; color: var(--text); outline: none; transition: border-color 0.2s; }
.form-control:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(30, 64, 175, 0.15); }

.filter-bar {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow);
}

.modal {
  display: none;
  position: fixed;
  top: 0; left: 0; width: 100%; height: 100%;
  background: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(2px);
  z-index: 1000;
  align-items: center; justify-content: center;
}
.modal.active { display: flex; }
.modal-content { background: #ffffff; border-radius: var(--radius); width: 90%; max-width: 550px; max-height: 90vh; overflow-y: auto; box-shadow: var(--shadow-lg); border: 1px solid var(--border); }
.modal-header { padding: 1.25rem 1.5rem; border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; }
.modal-title { font-size: 1.15rem; font-weight: 600; }
.modal-close { background: transparent; border: none; font-size: 1.5rem; cursor: pointer; color: var(--secondary); }
.modal-body { padding: 1.5rem; }
.modal-footer { padding: 1rem 1.5rem; border-top: 1px solid var(--border); display: flex; justify-content: flex-end; gap: 0.75rem; background: #f8fafc; }

.toast-container { position: fixed; bottom: 2rem; right: 2rem; z-index: 2000; display: flex; flex-direction: column; gap: 0.5rem; }
.toast { padding: 0.85rem 1.25rem; border-radius: var(--radius); background: #1e293b; color: #ffffff; font-size: 0.9rem; box-shadow: var(--shadow-lg); display: flex; align-items: center; gap: 0.75rem; animation: slideUp 0.25s ease-out; }
.toast.success { background: #065f46; }
.toast.error { background: #991b1b; }
.toast.warning { background: #92400e; }

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

@media print {
  .navbar, .sidebar, .btn, .filter-bar, .modal, .toast-container { display: none !important; }
  body, .main-content { background: #ffffff !important; padding: 0 !important; }
  .card, .table-container { box-shadow: none !important; border: 1px solid #000000 !important; }
}