.sidebar {
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
}
.nav-link {
    padding: 10px 15px;
    border-radius: 5px;
    margin-bottom: 3px;
}
.nav-link:hover {
    background-color: #495057;
}
.card {
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}