body {
    background-color: #f8f9fa;
}

.navbar {
    margin-bottom: 20px;
}

.card {
    border-radius: 15px;
    box-shadow: 0 4px 8px 0 rgba(0,0,0,0.2);
    transition: 0.3s;
}

.card:hover {
    box-shadow: 0 8px 16px 0 rgba(0,0,0,0.2);
}

.card-header {
    background-color: #343a40;
    color: white;
    border-top-left-radius: 15px;
    border-top-right-radius: 15px;
}

.btn-primary {
    background-color: #007bff;
    border-color: #007bff;
}

.btn-primary:hover {
    background-color: #0056b3;
    border-color: #0056b3;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding-left: 15px;
        padding-right: 15px;
    }
    h1 {
        font-size: 1.75rem;
    }
    .card {
        margin-bottom: 15px;
    }
}