body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #f8f9fa;
}
.sidebar {
  height: 100vh;
  border-right: 1px solid #ddd;
}
.nav-link {
  font-weight: 500;
}
.nav-link.active {
  color: #0d6efd;
}