body {
    background-color: #f4f6f9;
}

.sidebar {
    width: 250px;
    min-height: 100vh;
    background-color: #1f2937;
}

.sidebar a {
    color: white;
    text-decoration: none;
    display: block;
    padding: 12px 20px;
}

.sidebar a:hover {
    background-color: #374151;
}

.main-content {
    padding: 20px;
}

.topbar {
    background: white;
    padding: 15px;
    border-bottom: 1px solid #ddd;
}

.card-stat {
    border-left: 5px solid #0d6efd;
}